Post on 13-Mar-2021
1 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
A Day in the Life of an L2/L3 TSN Data Packet. Norman Finn
Mar. 5, 2014
Version 2
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 2 IEEE 802 Plenary meeting, Beijing China, March 2014
• This presentation, tsn-nfinn-Day-In-The-Life-0214-v02 is an annex to a two-part presentation.
• Part 1, tsn-nfinn-L2-Data-Plane-0214-v04, introduces concepts on which these presentations depend.
• Part 2, tsn-nfinn-L3-Data-Plane-0214-v03, is concerned with Layer 3 issues.
• See also cb-nfinn-How-Many-VLANs-0214-v02.
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 3 IEEE 802 Plenary meeting, Beijing China, March 2014
1. A very brief introduction, using concepts introduced in the preceding decks, followed by 6 “A Day In The Life Of A Packet” case studies.
2. Case 1: End-to-end Sequenced TSN encaps. 3. Case 2: Mixed L2/L3 IPgram pseudowire encaps. 4. Case 3: IPgram pseudowire to Sequenced TSN
Stitching. 5. Case 4: IEC 62439-3 HSR or PRP encaps. 6. Case 5: End-to-end Ethernet-over-XYZ tunnels. 7. Case 6: IP Multicast encaps. 8. A one-slide summary of conclusions is given.
4 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 5 IEEE 802 Plenary meeting, Beijing China, March 2014
Higher Layers
Circuit Encaps/Decaps
Sequencing
Split / Merge
D E
S M
Q V
L2-Data-Plane• Higher Layers work as
always. • “Sequencing” numbers
packets , and discards duplicates .
• Split /Merge has one circuit ID above and two below its layer.
• Circuit Encaps /Decaps marks individual circuits.
Q
E D
S M
V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 6 IEEE 802 Plenary meeting, Beijing China, March 2014
• This is the stack for a bridge that proxies for a non-TSN client, e.g. Bridge 8 in the following examples:
L2-Data-Plane
Proxy services bridge baggy pants diagram
PHY 1 MAC 1
Bridge relay
Circuit Detection
TSN Encaps/Decaps Split/Merge Sequencing
MAC 2 PHY 2
VLAN
VLAN
7 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 8 IEEE 802 Plenary meeting, Beijing China, March 2014
•Top-down view
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 9 IEEE 802 Plenary meeting, Beijing China, March 2014
TSN tagging
• Given that introduction, let us examine the simplest case: end-to-end connectivity through a Bridged LAN.
L T 2 6
7 8
4
5 3
1
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 10 IEEE 802 Plenary meeting, Beijing China, March 2014
TSN tagging
• Talker is TSN-aware, Listener is not. • Talker is not VLAN-aware, Listener is VLAN-
aware.
L T 2 6
7 8
4
5 3
1
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 11 IEEE 802 Plenary meeting, Beijing China, March 2014
• Without TSN, the bridges bridge.
L T 2 6
7 8
4
5 3
1
data
SA: Talker T
DA: Listener L
ET: whatever
data
ET: whatever
SA: Talker T
DA: Listener L
VLAN 80
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 12 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 2 6
7 8
4
5 3
1
• Talker T and Listener L have a higher layer relationship.
I I
I
data
ET: whatever
SA: Talker T
DA: Listener L
VLAN 80
data
SA: Talker T
DA: Listener L
ET: whatever
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 13 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 2 6
7 8
4
5 3
1
• The operator wants Talker T and Listener L to have a TSN circuit relationship , , (734[99]) so that they can get the TSN QoS. (The bridges need the circuit ID in order to provide the TSN QoS.)
I I E D
D E
data
ET: whatever
SA: Talker T
DA: Listener L
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
data
SA: Talker T
DA: Listener L
circuit_ID
ET: whatever
VLAN 80
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 14 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 2 6
7 8
4
5 3
1
• But, the Listener is TSN-unaware, so Bridge 8 has to provide the TSN Circuit Decaps as a proxy service.
I I E D
D
data
ET: whatever
SA: Talker T
DA: Listener L
VLAN 80
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
data
SA: Talker T
DA: Listener L
circuit_ID
ET: whatever
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 15 IEEE 802 Plenary meeting, Beijing China, March 2014
E
1
D
E L T
2 6
7 8
4
5 3
• The operator wants Sequencing proxied for T and L by Router 1 and Bridge 8, and seq. ecaps .
8 I I
Q
E
data
ET: whatever
seq_number
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
data
ET: whatever
SA: Talker T
DA: Listener L
VLAN 80
V
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
Sequence #
ET: TSN Seq
SA: Talker T
DA: Listener L
VLAN 80
Q
circuit_ID
data
SA: Talker T
DA: Listener L
circuit_ID
ET: whatever
E D
D D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 16 IEEE 802 Plenary meeting, Beijing China, March 2014
• We want Split and Merge functions , for seamless redundancy where the circuit bifurcates.
L T 2 6
7 8
4
5 3
1
8 I I E
data
ET: whatever
SA: T
DA: L
VLAN 80
data
SA: T
DA: TSN 7840
ET: whatever
VLAN tag 23
Sequence #
ET: TSN Seq
S M
data
DA: L
Sequence #
circuit_ID
data
SA: T
DA: TSN 12
ET: whatever
VLAN tag 50
Sequence #
ET: TSN Seq
data
SA: Talker T
DA: Listener L
circuit_ID
ET: whatever
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
E D S
E M D
D
Q V
SA: T
vlan_ID 80
ET: whatever
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 17 IEEE 802 Plenary meeting, Beijing China, March 2014
1 T
• Why is this TSN Decaps function upside down?
• Because it peers with Talker T’s TSN Encaps function.
E
E S E
D
Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 18 IEEE 802 Plenary meeting, Beijing China, March 2014
• This is a more accurate picture, but you can only get so much information on one slide.
higher layers
MAC VLAN TSN e
higher layers
MAC VLAN
MAC
circuit- sequence- aware relay
Seq v TSN d
virtual MAC MAC
802.1Q Relay
VLAN VLAN VLAN TSN d Merge
MAC
circuit- sequence- aware relay
Seq q TSN e
virtual MAC MAC
802.1Q Relay
VLAN VLAN VLAN TSN d TSN e
Split
VLAN VLAN
TalkerT Listener L Bridge 1 Bridge 8
E E D S E
M D
D
Q V
1 8 T L
Host proxy Host proxy
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 19 IEEE 802 Plenary meeting, Beijing China, March 2014
• In this example, the Circuit Encaps is in the Talker system (above the link).
• And the Sequencing is in Bridge 1 (below the link).
Circuit Encaps
Sequencing
Higher Layers
E
Q
Circuit Decaps
D
Circuit Encaps
E
Split S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 20 IEEE 802 Plenary meeting, Beijing China, March 2014
• In this example, the Listener system is TSN-unaware.
• And the Sequencing, Merge, and TSN Decaps are all in Bridge 8 (below the link).
Sequencing
Higher Layers
Circuit Decaps
Merge
D
M
V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 21 IEEE 802 Plenary meeting, Beijing China, March 2014
•Day-in-the-life view
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 22 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• Talker’s stack is not VLAN-aware. This is what the frame is when it hits the TSN Encaps layer.
• Note that Bridge 1 would normally add a VLAN 80 tag to this frame.
IPgram
SA: T
DA: L
circuit_identifier
ET: IP
L T 2 6
7 8
4
5 3
1 8 I I E
D
E D S E Q
M D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 23 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• Talker is TSN-aware, so the TSN Encaps layer adds a VLAN tag, even though Talker’s stack is not VLAN-aware.
• Talker could add sequence number, but doesn’t.
IPgram
SA: T
DA: TSN 734
ET: IP
VLAN tag 99
E
L T 2 6
7 8
4
5 3
1 8 I I E
D
E D S E Q
M D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 24 IEEE 802 Plenary meeting, Beijing China, March 2014
• The Sequencing function adds a new TSN sequence number.
• (Notionally, the DA/VLAN have been restored. In practice, one would not bother.)
Q
Sequenced TSN tagging
circuit_identifier 734[99]
data
SA: T
DA: L
vlan_identifier 80
L T 2 6
7 8
4
5 3
1 8 I I E
sequence_number ET: whatever
E D S E M
D V
D
Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 25 IEEE 802 Plenary meeting, Beijing China, March 2014
• The Sequencing encaps function replaces the sequence_number parameter with a new TSN sequence number tag, to be defined by IEEE 802.1.
E
Sequenced TSN tagging
circuit_identifier 734[99]
data
ET: whatever
SA: T
DA: L
Sequence #
vlan_identifier 80
ET: TSN Seq
L T 2 6
7 8
4
5 3
1 8 I I E
E D S M D V
D
E Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 26 IEEE 802 Plenary meeting, Beijing China, March 2014
E
L T 2 6
7 8
4
5 3
1 I I E
Sequenced TSN tagging
data
ET: whatever
SA: T
DA: L
Sequence #
vlan_identifier 80
ET: TSN Seq
S
circuit_ID 7840[23] or 12[50]
D
D M D V
• The Split function creates two packets, with different circuit_identifiers.
S E Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 27 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• After being encoded, again, this is the Ethernet frame on the upper path.
L T 2 6
7 8
4
5 3
1
data
SA: T
DA: TSN 7840
ET: whatever
VLAN tag 23
I I
Sequence #
ET: TSN Seq
E
E
E
D
D S E Q
M D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 28 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• Note that we have a different circuit ID on the second path.
• Another presentation is required to discuss whether the DA, the VLAN, both, or neither, should be different.
L T 2 6
7 8
4
5 3
1
data
SA: T
DA: TSN 12
ET: whatever
VLAN tag 50
I I
Sequence #
ET: TSN Seq
E
E
D
D S E Q
M D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 29 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• The TSN Decaps function restores the proper DA and VLAN, and extracts the circuit_identifier.
L T 2 6
7 8
4
5 3
1 I I E
circuit_ID 7840[23] or 12[50]
data
ET: whatever
SA: T
DA: L
Sequence #
ET: TSN Seq
data
ET: whatever
Sequence #
vlan_identifier 80
ET: TSN Seq
E
D
D S E Q
D
M D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 30 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• The Merge function takes all packets and gives them the same circuit_identifier.
• (It is the same as on the Talker T to Bridge 1 link.)
• (There are still 2 packets.)
L T 2 6
7 8
4
5 3
1 I I E
circuit_identifier 734[99]
data
ET: whatever
SA: T
DA: L
Sequence #
vlan_identifier 80
ET: TSN Seq
M
E
D
D S E Q
M D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 31 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• The Sequencing Decapsulation function exposes the sequence_ number so that the Sequence Discard function can discard the duplicates.
• (There are still 2 packets.)
L T 2 6
7 8
4
5 3
1 I I E
circuit_identifier 734[99]
data
SA: T
DA: L
vlan_identifier 80
sequence_number
E
D
D S E Q
M D
D
V
ET: whatever
V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 32 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequenced TSN tagging
• A single frame is output from Sequencing function .
• It is what would have come from the Talker, modulo the VLAN tag changes the bridges would make.
L T 2 6
7 8
4
5 3
1
data
SA: T
ET: whatever
I I E
VLAN tag 80
DA: L V
E
D
D S E Q
M D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 33 IEEE 802 Plenary meeting, Beijing China, March 2014
Summary:
L T 2 6
7 8
4
5 3
1 I I E
E D S E M
D
• This uses the full Split/Merge functionality with different cicuit_identifiers on the paths.
data
ET: whatever
SA: T
DA: L
VLAN 80
data
SA: T
DA: TSN 7840
ET: whatever
VLAN tag 23
Sequence #
ET: TSN Seq
data
SA: T
DA: TSN 12
ET: whatever
VLAN tag 50
Sequence #
ET: TSN Seq
data
SA: Talker T
DA: Listener L
circuit_ID
ET: whatever
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
V
D
Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 34 IEEE 802 Plenary meeting, Beijing China, March 2014
Variant 1:
L T 2 6
7 8
4
5 3
1 I I E E D E D
• This uses the full Split/Merge functionality with different cicuit_identifiers on the paths.
data
ET: whatever
SA: T
DA: L
VLAN 80
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
Sequence #
ET: TSN Seq
data
SA: Talker T
DA: Listener L
circuit_ID
ET: whatever
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
V
D
Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 35 IEEE 802 Plenary meeting, Beijing China, March 2014
Variant 2:
L T 2 6
7 8
4
5 3
1 I I D D
• If Talker T does the sequencing and encaps, and all paths use the same encaps, it gets really simple!
data
ET: whatever
SA: T
DA: L
VLAN 80
data
SA: T
DA: TSN 734
ET: whatever
VLAN tag 99
Sequence #
ET: TSN Seq
data
SA: Talker T
DA: Listener L
circuit_ID
ET: whatever
V
E E Q
36 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 37 IEEE 802 Plenary meeting, Beijing China, March 2014
L T
TSN aware Talker
Router Split LER
Bridge
Bridges Bridge Merge
1
5
LER / Router
LER/router
• Single-port TSN- VLAN-aware Talker T and a single-port TSN- VLAN-unaware Listener L.
• The Talker sequences , and peers to the Discard in Bridge 8.
• Talker attached to a router; Listener to a bridge. • A network with a variety of routers and bridges.
2 6
7 3
4 8
LSR / Router
TSN unaware Listener
I I V Q
V Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 38 IEEE 802 Plenary meeting, Beijing China, March 2014
L T Bridge 1
5 LER/router
2 6
7 3
4 8 I I
IPgram
pseudowire label 28
control (sequence) • Talker T and Bridge 8 have
chosen to use an IPgram pseudowire for the circuit.
E D Q V
E D
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 39 IEEE 802 Plenary meeting, Beijing China, March 2014
L T
TSN aware Talker
Router Split LER
Bridge
Bridges Bridge Merge
1
5
LER / Router
LER/router
• Router 1 and Bridge 8 are the split/merge (seamless redundancy) peers, because they split and merge the circuits.
• (Inserting the Split function in Router 1 requires an extra Encode/Decode pair.)
2 6
7 3
4 8
LSR / Router
TSN unaware Listener
S
M
I I
D
E E D M
S Q V
D
E
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 40 IEEE 802 Plenary meeting, Beijing China, March 2014
L T
TSN aware Talker
Router Split LER
Bridge
Bridges Bridge Merge
1
5
LER / Router
LER/router
• Assuming that the encode/decode used by the Split/Merge are pseudowires, we require a network of Label Switched Paths (LSPs) to connect T to to . Each endpoint is a Label Edge Router (LER) function.
2 6
7 3
4 8
LSR / Router
TSN unaware Listener
I I
L
L
L
L
S M
S M
L
L
D
E E
D
S Q
L M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 41 IEEE 802 Plenary meeting, Beijing China, March 2014
• TSN Circuit Encaps/Decaps pairs are needed to convey the circuit over the various Bridged LANs. (Note the blue, instead of purple, letter and outline.)
E
D
L T
TSN aware Talker
Router Split LER
Bridge
Bridges Bridge Merge
1
5
LER / Router
LER/router 2 6
7 3
4 8
LSR / Router
TSN unaware Listener
I I
D E
E L
L L
D
E E S
Q
L
E D L
D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 42 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
IPgram • Talker T has an IPgram to send to Listener L.
L T 1
5
2 6
7 3
4 8 I I
E D
L
L
D
E E S
Q
L
L
E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 43 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
pseudowire label 28
control (sequence)
IPgram pseudowire
• Talker T’s combined TSN Encaps and Sequencing functions use an IPgram pseudowire for the circuit.
• Bridge 8’s functions are at the other end of the network.
L T 1
5
2 6
7 3
4 8 I I
E D
E
D
Q
V L
L
D
E S
L
L E Q
E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 44 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
pseudowire label 28
control (sequence)
IPgram pseudowire
• In the general case, the LER function would encapsulate the pseudowire would be carried in an LSP.
L T 1
5
2 6
7 3
4 8 I I
E D
label 60
L
L
L
D
E S
L
L E Q
E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 45 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
pseudowire label 28
control (sequence)
IPgram pseudowire
• In this particular case, we will assume that Router 1 is doing a “Penultimate Hop Pop” (PHP) function. That eliminates the need for the outside label encaps .
L T 1
5
2 6
7 3
4 8 I I
E D
label 60
D
E S
L
L E Q
L
L
E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 46 IEEE 802 Plenary meeting, Beijing China, March 2014
• The PHP step may be controversial. • Perhaps there is another MPLS label, a path
label, on the frame between the Talker and Router 1.
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 47 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
pseudowire label 28
control (sequence)
IPgram pseudowire
• So, the frame from Talker T to Router 1 looks like this on the Ethernet between Talker T and Router 1.
L T 1
5
2 6
7 3
4 8 I I
E D
SA: T
DA: Router 1
ET: MPLS
E Q
D
E S L
L E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 48 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
IPgram
circuit_ID (psw 28)
sequence_# (control) • The Splitter function in
Router 1 is given the IPgram.
L T 1
5
2 6
7 3
4 8 I I
E D
S
E Q
D
E S L
L E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 49 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
IPgram
• The Splitter function has split the one pseudowire 28 into two pseudowires 419 and 31, copying the one control word to both of them.
L T 1
5
2 6
7 3
4 8 I I
E D
S
IPgram
E Q
D
E
circuit_ID (psw 419)
sequence_# (control)
circuit_ID (psw 31)
sequence_# (control)
S L
L E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 50 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• The TSN Encapsulation function (an IPgram pseudowire encaps) generates these two packets, ready to enter the two LSPs.
L T 1
5
2 6
7 3
4 8 I I
E D
E Q
D
L
L E
E
D L D M V
E S
IPgram
pseudowire label 31
control (sequence)
IPgram
pseudowire label 419
control (sequence) E
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 51 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
IPgram
pseudowire label 419
control (sequence)
• The upper tunnel looks like this, when labeled with Tunnel 51, and before applying the TSN Encapsulation. This would be the usual Ethernet frame from Router 1 to Router 4
Tunnel label 51
L T 1
5
2 6
7 3
4 8 I I
E D
SA: Router 1
DA: Router 4
vlan_identifier 15
circuit_identifier
E Q
D
E S L
L E
E
D L D M V
ET: MPLS
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 52 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• But, Router 1 and Router 4 are separated by a TSN bridged network, so require a TSN encapsulation .
• This gets the packet to Router 4.
L T 1
5
2 6
7 3
4 8 I I
E D
SA: Router 1
DA: TSN 140
IPgram
pseudowire label 419
control (sequence)
Tunnel label 51
ET: MPLS
VLAN tag 309
E D
E Q
D
E S L
L E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 53 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• Meanwhile, Router/LER 1, Router/LSR 3 and Router/LSR 5 are moving the second LSP packet along.
• No TSN encaps is needed in the absence of bridges.
L T 1
5
2 6
7 3
4 8 I I
E D
SA: Router 1
DA: Router 3
IPgram
pseudowire label 31
control (sequence)
Tunnel label 557
ET: MPLS
E Q
D
E S L
L E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 54 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• Meanwhile, Router/LER 1, Router/LSR 3 and Router/LSR 5 are moving the LSP packet along.
• Router/LSR 3 changes the Tunnel label 557346.
L T 1
5
2 6
7 3
4 8 I I
E D
SA: Router 3
DA: Router 5
IPgram
pseudowire label 31
control (sequence)
Tunnel label 346
ET: MPLS
E Q
D
E S L
L E
E
D L D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 55 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• After TSN decapsulation , Router 4 has this labeled packet.
• And Router 5 has this one.
L T 1
5
2 6
7 3
4 8 I I
E D
IPgram
pseudowire label 419
control (sequence)
Tunnel label 51
IPgram
pseudowire label 31
control (sequence)
Tunnel label 346
E Q
D
E S L
L E
E
D L D M V
D
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 56 IEEE 802 Plenary meeting, Beijing China, March 2014
1
IPgram pseudowire
• For the sake of reduced frame size, Router/LSPs 4 and 5 perform PHP, which eliminates Tunnel labels 51 and 346 (and the LERs in Bridge 8).
L T 5
2 6
7 3
4 8 I I
E D
IPgram
pseudowire label 419
control (sequence)
L
IPgram
pseudowire label 31
control (sequence)
L
L
E Q
D
E S L
L E
E
D D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 57 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• One can argue the semantics of the green tunnels. In theory, each tunnel continues to its natural end at Bridge 8. The control plane may maintain this. But, in the data plane, the tunnel label disappears.
• So, we will shorten the tunnel in the diagram to match the data plane encapsulation
L T 1
5
2 6
7 3
4 8 I I
E D L
L
E Q
D
E S L
L E
E
D D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 58 IEEE 802 Plenary meeting, Beijing China, March 2014
SA: Router 4
DA: Listener L
IPgram
pseudowire label 419
control (sequence)
vlan_identifier 80
ET: MPLS
IPgram pseudowire
• Router 4 prepares this Ethernet frame to transmit the pseudowire packet.
L T 1
5
2 6
7 3
4 8 I I
D E
L
L
E Q
D
E S L
L E
E
D D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 59 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• And Router 4’s TSN Encaps function produces this. SA: Router 4
DA: TSN 994
VLAN tag 7
L T 1
5
2 6
7 3
4 8 I I
D E
L
L
E Q
D
E S L
L E
E
D D M V
IPgram
pseudowire label 419
control (sequence)
E
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 60 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• And IPgram pseudowire label 31 is translated by Router 5’s TSN Encaps into this.
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L E
E
D D M V
SA: Router 5
DA: TSN 2006
VLAN tag 18
IPgram
pseudowire label 31
control (sequence)
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 61 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• The TSN Decaps function exposes the pseudowire and restores the Ethernet frame parameters.
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
SA: Router 4 or 5
vlan_identifier 80
circ_ID 994[7] or 2006[18]
DA: Listener L
E
E
D D M V
8
D
IPgram
pseudowire label 419
control (sequence)
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 62 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• The Merge function has to operate on the circuit and sequence number after the pseudowire Decaps function makes these parameters available (and adds the IP EtherType).
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
M
E Q
D
E S L
L
D
IPgram
SA: Router 4 or 5
vlan_identifier 80
circuit_ID psw 419 or 31
sequence_number ET: IP
DA: Listener L
E
E
D D 8 M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 63 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• Output from Merge function • Pseudowire labels 419 and
31 have been combined into the original pseudowire label 28.
• There are still two packets!
M
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
IPgram
SA: Router 4 or 5
vlan_identifier 80
circuit_ID psw 28
sequence_number ET: IP
DA: Listener L
E
E
D D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 64 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• The Sequencing Discard function then deletes the redundant frames, passing whichever (from Router 4, in this case) happens to arrive, first.
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
IPgram
V DA: Listener L
SA: Router 4
vlan_identifier 80
circuit_ID psw 28
sequence_number ET: IP
E
E
D D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 65 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram pseudowire
• When the frame is put on the wire to Listener L, the circuit_identifier and sequence_number are discarded, and the remaining parameters make the frame.
IPgram
SA: Router 4
ET: IP
VLAN tag 80
DA: L
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L E
E
D D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 66 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
SUMMARY:
IPgram
Pseudowire 28
control (seq)
SA: T
DA: Router 1
ET: MPLS
SA: Router 1
DA: TSN 140
IPgram
Pseudowire 449
control (seq)
Tunnel 51
ET: MPLS
VLAN tag 309 SA: Router 3
DA: Router 5
IPgram
Pseudowire 31
control (seq)
Tunnel 346
ET: MPLS
IPgram
ET: IP
SA: Router 4
DA: Listener L
VLAN tag 80
E Q
D
E S L
L E
E
D D M V
IPgram
SA: Router 4
DA: TSN 994
VLAN tag 7
Pseudowire 419
control (seq)
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 67 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
Variant 3:
E Q
D
E S L
L E
E
D D M V
IPgram
Pseudowire 28
control (seq)
SA: T
DA: Router 1
ET: MPLS
SA: Router 1
DA: TSN 140
IPgram
Pseudowire 28
control (seq)
Tunnel 51
ET: MPLS
VLAN tag 309 SA: Router 3
DA: Router 5
IPgram
Pseudowire 28
control (seq)
Tunnel 346
ET: MPLS
IPgram
ET: IP
SA: Router 4
DA: Listener L
VLAN tag 80
IPgram
SA: Router 4
DA: TSN 994
VLAN tag 7
Pseudowire 28
control (seq)
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 68 IEEE 802 Plenary meeting, Beijing China, March 2014
Variant 3:
• Note that the Split function is still present, in this case, because pseudowire duplication is not a function that is built into the data plane. It does not create new pseudowire labels, though.
• But, the Merge function is now a no-op.
S
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L E
E
D D M V
M
69 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 70 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
• Ignoring the lower layers, for a moment, we have the pair in Talker T peering with the pair in Bridge 8.
E Q
D V
E Q
D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 71 IEEE 802 Plenary meeting, Beijing China, March 2014
• In the left-hand world, we want the Circuit ID Encaps/Decaps to be an IPgram pseudowire, because it is the “natural” format for a router.
IPgram
pseudowire label 419
control (sequence)
L T 1
5
2 6
7 3
4 8 I I E
Q D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 72 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
SA: Router 4
DA: TSN 7840
ET: IP
VLAN tag 23
Sequence #
ET: TSN Seq
• In the right-hand world, we want the Circuit ID Encaps/Decaps to be the Serialized TSN encaps, because it is the “natural” format for a Bridge.
L T 1
5
2 6
7 3
4 8 I I E
Q D V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 73 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
pseudowire label 419
control (sequence)
IPgram
SA: Router 4
DA: TSN 7840
ET: IP
VLAN tag 23
ET: TSN Seq
• An Interworking function carries the Sequence number across the gap.
Sequence # W
L T 1
5
2 6
7 3
4 8 I I E
Q D V
W
W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 74 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I E
Q D V
• The Interworking Functions enable the TSN Pseudowire Encaps function and the Sequenced TSN Decaps function at the very ends of the network to be peers, just like the Sequenced TSN and IPgram pseudowire end-to-end cases.
W
E
D
W
W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 75 IEEE 802 Plenary meeting, Beijing China, March 2014
Higher layers
Seq TSN Circuit Encaps/Decaps
Higher layers
Pseudowire Circuit Encaps/Decaps
Talker side Listener side
• We have two differet protocol stacks, pseudowire and sequenced TSN, that perform essentially the same function.
• We want them to peer with each other.
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 76 IEEE 802 Plenary meeting, Beijing China, March 2014
Higher layers Higher layers
Talker side Listener side
• Note that we are not including the sublayers that act on the sequence numbers.
Sequencing
Higher layers
Seq TSN Circuit Encaps/Decaps
Sequencing
Higher layers
Pseudowire Circuit Encaps/Decaps
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 77 IEEE 802 Plenary meeting, Beijing China, March 2014
Sequence- and Circuit-aware Relay
Talker side Listener side
• If we connect these two stacks with a trivial two-port relay that carries the sequence_number and circuit_identifier parameters intact, . . .
Seq TSN Circuit Encaps/Decaps
Pseudowire Circuit Encaps/Decaps
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 78 IEEE 802 Plenary meeting, Beijing China, March 2014
Pseudowire / Sequenced TSN Interworking function
Sequence- and Circuit-aware Relay
Talker side Listener side
• . . . we have an “interworking function.” • We’ll show the interworking relay as , and
the whole interworking function as .
W
Seq TSN Circuit Encaps/Decaps
Pseudowire Circuit Encaps/Decaps D E D E
D E W
W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 79 IEEE 802 Plenary meeting, Beijing China, March 2014
• Returning to our previous discussion, we were peering IPgram pseudowire encapsulations at both ends.
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L E
E
D D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 80 IEEE 802 Plenary meeting, Beijing China, March 2014
• On the right hand side, we eliminate the simple TSN encaps used to carry the pseudowire, and replace the IPgram pseudowire encaps with the Sequenced TSN enaps that we want.
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L D M V
E D
E
E
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 81 IEEE 802 Plenary meeting, Beijing China, March 2014
• On the left hand side, we supply termination for the IPgram pseudowire encaps used by Talker T.
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L D M V
E
E
D
D
E
D
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 82 IEEE 802 Plenary meeting, Beijing China, March 2014
• When we add the interworking relay ,the IPgram pseudowire / Sequenced TSN Stitching Interworking Function cements the gap.
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L D M V
E
E
D
D
W
W
W
E D W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 83 IEEE 802 Plenary meeting, Beijing China, March 2014
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D E
E Q
D
E S L
L D M V
• At this point in the end-to-end IPgram pseudowire description, we had the “naked” pseudowire packets in Routers 4 and 5.
IPgram
pseudowire label 419
control (sequence)
IPgram
pseudowire label 31
control (sequence)
L
L
E D W
E D W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 84 IEEE 802 Plenary meeting, Beijing China, March 2014
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D E
E Q
D
E S L
L D M V
• These packets are decapsulated.
IPgram
circuit_ID 419/7840[23]
sequence_number
IPgram
circuit_ID 31/12[50]
sequence_number
L
L
E D
E D
W
W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 85 IEEE 802 Plenary meeting, Beijing China, March 2014
IP Pseudo / TSN Stitching
• And when re-encapsulated by the Sequenced TSN Encaps , the packet in Router 4 becomes 7840[23].
IPgram
SA: Router 4
DA: TSN 7840
ET: IP
VLAN tag 23
Sequence #
ET: TSN Seq
L T 1
5
2 6
7 3
4 8 I I
D E
L
L
E Q
D
E S L
L
E
D M V
D E W
D E W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 86 IEEE 802 Plenary meeting, Beijing China, March 2014
IP Pseudo / TSN Stitching
• And IPgram pseudowire label 346 is translated by Router 5’s Interworking function into TSN circuit 12[50].
IPgram
SA: Router 5
DA: TSN 12
ET: IP
VLAN tag 50
Sequence #
ET: TSN Seq
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
D E W
D M V
D E W
D E W
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 87 IEEE 802 Plenary meeting, Beijing China, March 2014
IP Pseudo / TSN Stitching
• The TSN Decaps function unwraps the circuit_identifier and sequence_number, and restores the Ethernet frame parameters.
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
IPgram
SA: Router 4 or 5
vlan_identifier 80
circuit_ID 7840[23] or 12[50]
sequence_number ET: IP
DA: Listener L
D E W
D E W D
D
M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 88 IEEE 802 Plenary meeting, Beijing China, March 2014
IP Pseudo / TSN Stitching
• Output from Merge function • TSN circuit IDs 7840[23] and
12[50] have been combined, but there are still 2 packets.
• To Bridge 8, this is the end-to-end circuit from Talker T.
M
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
IPgram
SA: Router 4 or 5
vlan_identifier 80
circuit_ID xyz
sequence_number ET: IP
DA: Listener L
D E W
D E W D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 89 IEEE 802 Plenary meeting, Beijing China, March 2014
• The Sequencing Discard function passes only one of the frames.
• The circuit_identifier and sequence_number are no longer needed.
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
D E W
D E W D M V
IPgram
SA: Router 4
vlan_identifier 80
ET: IP
DA: Listener L
V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 90 IEEE 802 Plenary meeting, Beijing China, March 2014
• After discarding the unused parameters and converting the rest to the appropriate frame, this is what is output to Listener L.
IPgram
ET: IP
SA: Router 4
DA: Listener L
IP Pseudo / TSN Stitching
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
D E W
D E W D M V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 91 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
D E W
D E W D M V
SUMMARY:
IPgram
ET: IP
SA: Router 4
DA: Listener L
IPgram
Pseudowire 28
control (seq)
SA: T
DA: Router 1
ET: MPLS
SA: Router 1
DA: TSN 140
IPgram
Pseudowire 449
control (seq)
Tunnel 51
ET: MPLS
VLAN tag 309 SA: Router 3
DA: Router 5
IPgram
Pseudowire 31
control (seq)
Tunnel 346
ET: MPLS
IPgram
SA: Router 5
DA: TSN 12
ET: IP
VLAN tag 50
Sequence #
ET: TSN Seq
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 92 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
D
L
E L
E Q
D
E S L
L
D E W
D E W
D V
Variant 4: 1 CIRCUIT
IPgram
ET: IP
SA: Router 4
DA: Listener L
IPgram
Pseudowire 28
control (seq)
SA: T
DA: Router 1
ET: MPLS
SA: Router 1
DA: TSN 140
IPgram
Pseudowire 28
control (seq)
Tunnel 51
ET: MPLS
VLAN tag 309 SA: Router 3
DA: Router 5
IPgram
Pseudowire 28
control (seq)
Tunnel 346
ET: MPLS
IPgram
SA: Router 5
DA: TSN 12
ET: IP
VLAN tag 50
Sequence #
ET: TSN Seq
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 93 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
pseudowire label 28
control (sequence)
Variant 5:
• Talker T could be dual-homed. • In this case, clearly T must
supply the sequence numbers. • The sequence numbers are
usually part of the encapsulation. • So, T terminates the pseudowire,
not routers 2 and 3.
L T 2 6
7 3 8 I I
E
E 2 S
Q L
L
Ω
D D M V
5
4 D
E
E L
L
94 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 95 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR tagging
• Again, Talker is TSN-aware, Listener is not. • This time, Talker is not VLAN-aware,
Listener is VLAN-aware. • In this case, HSR and TSN Encaps and
Decaps are combined into a single layer.
L T 2 6
7 8
4
5 3
1 I I E
D
D
E
Q M V
D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 96 IEEE 802 Plenary meeting, Beijing China, March 2014
• This is not HSR. It is the HSR format used for a different purpose. This idea may or may not sit well with IEC TC65X.
• This “HSR-like” layer: Connects to a single port, not two. May use one sequence number variable per
circuit, not one per host. (This is debatable.) If the station is VLAN aware, has the VLAN
tagging below (outside) the HSR sublayer.
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 97 IEEE 802 Plenary meeting, Beijing China, March 2014
• Note that this is the layering – the top box is Talker T, and the bottom box is Bridge 1.
• HSR combines the Circuit Encaps/Decaps and Sequencing functions.
• It also encapsulates the destination MAC address which, as we will see, is not really very useful.
Circuit Encaps/Decaps
Sequencing
Split / Merge
Higher Layers
HSR
host
bridge
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 98 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR-like tagging
• Talker’s stack is not VLAN-aware. This is what the frame is when it hits the TSN Encaps layer.
• Note that Bridge 1 would normally add a VLAN 80 tag to this frame.
L T 2 6
7 8
4
5 3
1
IPgram
SA: T
DA: L
I I
circuit_identifier
ET: IP
E D
Q M V
D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 99 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR-like tagging
• The Sequencing and combined HSR/TSN Encaps layer create a sequence number and add a TSN/HSR tag.
L T 2 6
7 8
4
5 3
1 I I
E
DA: TSN 734
VLAN tag 99
SA: T
EtherType
Data
HSR EtherType
pid, length, sequence
DA: L
E D
Q M V
Q
D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 100 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR-like tagging
• The Split function operates on the TSN header, for the path ID, and the HSR header, for the sequence number. (The “pid” field includes a “path
A / path B” flag that intended to be different between the two paths. We may or may not follow that usage.)
L T 2 6
7 8
4
5 3
1 I I
SA: T
DA: TSN 7840
VLAN tag 23
EtherType
Data
HSR EtherType
pid, length, sequence
DA: L
S DA: TSN 7840
VLAN tag 23
SA: T
EtherType
Data
HSR EtherType
pid, length, sequence
DA: L
E D
Q M V
D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 101 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR-like tagging
• The other path gets a different DA and VLAN tag.
• Note that the Split function split TSN 734[99] into TSN 7840[23] and 12[50].
L T 2 6
7 8
4
5 3
1 I I
SA: T
DA: TSN 12
VLAN tag 50
EtherType
Data
HSR EtherType
pid, length, sequence
DA: L
DA: TSN 12
VLAN tag 50
SA: T
EtherType
Data
HSR EtherType
pid, length, sequence
DA: L
E D
Q M V
D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 102 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR-like tagging
• The Merge function operates on the circuit_identifier exposed by the decapsulation function
L T 2 6
7 8
4
5 3
1 I I
M DA: Listener L
vlan_identifier 80
SA: Talker T
Data
circuit_ID 7840[23] or 12[50]
E D
Q M V
sequence_number
EtherType D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 103 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR-like tagging
• Output from Merge function is the original 734[99] tunnel that originated from Bridge 1.
• Two packets are present until the Sequencing Discard function discards one.
L T 2 6
7 8
4
5 3
1 I I E
D
Q M
DA: Listener L
vlan_identifier 80
SA: Talker T
Data
circuit_ID 734[99]
sequence_number
EtherType D
E S
V
V
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 104 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR-like tagging
• And this is delivered on the wire.
L T 2 6
7 8
4
5 3
1
IPgram
SA: T
ET: IP
I I
VLAN tag 80
DA: L
E D
Q M V
D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 105 IEEE 802 Plenary meeting, Beijing China, March 2014
HSR EtherType
pid, length, seq
L T 2 6
7 8
4
5 3
1 I I E
D
Q M V
D
E S
Summary:
DA: TSN 734
VLAN tag 99
SA: T
EtherType
Data
HSR EtherType
pid, length, seq
DA: L
SA: T
DA: TSN 7840
VLAN tag 23
DA: TSN 7840
VLAN tag 23
SA: T
EtherType
Data
DA: L
SA: T
DA: TSN 12
VLAN tag 50
EtherType
Data
HSR EtherType pid, length, sequence
DA: L
DA: TSN 12
VLAN tag 50
SA: T
EtherType
Data
HSR EtherType
pid, length, seq
DA: L
IPgram
SA: T
ET: IP
VLAN tag 80
DA: L
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 106 IEEE 802 Plenary meeting, Beijing China, March 2014
IPgram
pseudowire label 28
control (sequence)
Variant 5:
• Talker T could be dual-homed. • In this case, clearly T must
supply the sequence numbers. • The sequence numbers are
usually part of the encapsulation. • So, T terminates the pseudowire,
not routers 2 and 3.
L T 2 6
7 3 8 I I
E
E 2 S
Q L
L
Ω
D D M V
5
4 D
E
E L
L
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 107 IEEE 802 Plenary meeting, Beijing China, March 2014
PRP tagging
• PRP would work similarly. • This could be useful to
interoperate with existing deployments.
• A big issue with the PRP trailer is that you can’t tell what it’s position is in the tag layering.
L T 2 6
7 8
4
5 3
1 I I
SA: T
DA: TSN 12
pid, length, sequence
DA: TSN 12
VLAN tag 50
SA: T
EtherType
Data
HSR EtherType
E D
Q M V
D
E S
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 108 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 2 6
7 8
4
5 3
1 I I E
D
Q M V
D
E S
Summary:
IPgram
SA: T
ET: IP
VLAN tag 80
DA: L
DA: TSN 734
VLAN tag 99
SA: T
EtherType
Data
SA: T
DA: TSN 7840
VLAN tag 23
DA: TSN 7840
VLAN tag 23
SA: T
EtherType
Data
SA: T
DA: TSN 12
VLAN tag 50
DA: TSN 12
VLAN tag 50
SA: T
EtherType
Data
pid, length, seq
HSR EtherType
pid, length, seq
HSR EtherType
pid, length, seq
HSR EtherType
109 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 110 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
• You can always create end-to-end encapsulated Ethernet circuits using, for example, Ethernet pseudowire and/or PBB-TE MAC-in-MAC in the standard ways it’s done, today.
D V
D V
E Q
E Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 111 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
• The catch is that the Talker has a separate Ethernet port per TSN flow.
• This is not compatible with a simple IP stack; each port needs its own IP address.
D V
D V
E Q
E Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 112 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
• There are solutions to this classic “multi-homed IP host” problem.
• It would take some effort to make them compatible with our simple QoS purpose.
D V
D V
E Q
E Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 113 IEEE 802 Plenary meeting, Beijing China, March 2014
L T 1
5
2 6
7 3
4 8 I I
• And, of course, it still begs the question, “How are these packet encapsulated?”
• Again, there are many standard answers to that question.
D V
D V
E Q
E Q
114 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 115 IEEE 802 Plenary meeting, Beijing China, March 2014
• Assume for a moment that we do not need to transmit multiple copies on different paths, so we do not need the Sequencing functions.
• Then, all we need is a per-flow circuit_identifier on every packet, at both L2 and L3.
• IP Multicast can supply this, even if it cannot supply a sequence number.
V Q
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 116 IEEE 802 Plenary meeting, Beijing China, March 2014
• In general, an IP multicast flow is identified by the Multicast IP destination address and the (unicast) IP source address.
• There is a 32:1 mapping of IP multicast addresses to MAC Group DAs.
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 117 IEEE 802 Plenary meeting, Beijing China, March 2014
• If the network administrator and protocols can ensure that the IP multicast addresses are unique over the flows, no TSN encapsulation is necessary.
• Otherwise, the usual TSN encapsulation will solve the Bridges’ problems with multicast, and the Routers can easily identify the streams to apply TSN QoS.
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 118 IEEE 802 Plenary meeting, Beijing China, March 2014
• The normal IP Group address and VLAN may or may not be sufficient for Bridged TSN networks, but the TSN encapsulation fixes this.
L T 1
5
2 6
3 4
8 I I
D E
MC IPgram
SA: T
DA: Group Z
ET: IP
IPgram
ET: IP
SA: Router 4
DA: Group Z?
VLAN tag 80
E
D
SA: Router 1
DA: Group Z?
MC IPgram
VLAN tag 309?
ET: IP
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 119 IEEE 802 Plenary meeting, Beijing China, March 2014
• And, if the protocol carried in the IP Multicast packet has a sequence number, then of course, the IP Multicast format is sufficient, in the data plane, for seamless redundancy, as well.
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 120 IEEE 802 Plenary meeting, Beijing China, March 2014
• The IP multicast control protocols, of course, would need work.
L T 1
5
2 6
3 4
8 I I
D E
MC IPgram
SA: T
DA: Group Z
ET: IP
IPgram
ET: IP
SA: Router 4
DA: Group Z?
VLAN tag 80
E
D
SA: Router 1
DA: Group Z?
MC IPgram
VLAN tag 309?
ET: IP
7
V Q
E
121 tsn-nfinn-Day-In-The-Life-0214-v02.pdf IEEE 802 Plenary meeting, Beijing China, March 2014
tsn-nfinn-Day-In-The-Life-0214-v02.pdf 122 IEEE 802 Plenary meeting, Beijing China, March 2014
• The layering scheme in tsn-nfinn-L2-Data-Plane-0214-v04 works.
• There are existing protocols for carrying both all-L2 and mixed L2/L3 TSN circuits.
• There are other possibilities for creating TSN circuits: VxLAN, LISP, and dozens of as-yet proprietary schemes.
• A new IEEE 802.1 sequence number tag can handle Ethernet end-to-end seamless redundancy.
• Mixed L2/L3 seamless redundancy requires either: Selecting a single end-to-end L2+ split/merge format (e.g.
pseudowire); or An interworking function between L3 and L2 split/merge
technologies; or Creating explicit end-to-end Ethernet tunnels.
Thank you.