Internet Standards BasedMobile Messaging

Alan.Stebbens@openwave.com

Milt.Roselinsky@openwave.com

March, 2003

Openwave Systems Internet Standards Based Mobile Messaging

Introduction

• The Mobile Messaging experience differs from current Internet Email experience– Mobile user expects “push model” of message delivery– Devices have limited (and varied) media rendering

capabilities– Many mobile networks are bandwidth starved and

“unreliable”.

• Multiple solutions have appeared– New protocols are being invented– Interoperability is a challenge

• Internet Email protocols should be enhanced– to support mobile messaging requirements– meet the needs of mobile users

Openwave Systems Internet Standards Based Mobile Messaging

Mobile Message Flow

MobileClient

Server

MobileClient

(1)Submit msg

(2)Notification

(3)Retrieval request

(4)Retrieval request

• Current mobile messaging practices analyzed in draft-stebrose-lemonade-mmsarch-00.txt

• Mobile messaging and desktop messaging experience have many similarities and a number of key differences

• Push model using active notification

(5)Alert User

Openwave Systems Internet Standards Based Mobile Messaging

Mobile Messaging Requirements 1

• “Push” Delivery model– enabling messages to "just show up" on the device,

• Flexible addressing– RFC2822, E.164, and "short codes" addressing

• MIME-based encapsulation:– Large, multimedia message support

• End-to-end Delivery Reports and Read Reports • Content adaptation:

– Smart network model:• Client capabilities and profile discovery by the server• Automatic content adaptation upon retrieval

– Smart client model:• Client-directed message content type retrieval• Client-directed content adaptation and retrieval

• Device-independent presentation language– enable uniform presentation for both mobile and

fixed-line clients

Openwave Systems Internet Standards Based Mobile Messaging

Mobile Messaging Requirements 2

• Notifications filter– User configurable– Server-based filtering– SPAM control even more critical than for e-mail

• Message exchange with existing Internet email systems

• Mailbox support (network-based persistent storage)

• Network-based and/or application-based authentication

• Bandwidth saving features such as:– binary transfers– data compression– forward without download– streamlined client- server message submission and

retrieval– pipelining to reduce transaction counts and RTT latencies

Openwave Systems Internet Standards Based Mobile Messaging

What’s all the fuss about, can’t we already do this?

• Not today – Internet messaging needs some enhancements and adjustments

Internet Mobile Messaging Requirements:• email + notification + content adaptation

• gets us most of the way there• Solutions must comply with established Internet Protocol

requirements:• end-to-end connectivity• broad applicability • reuse of existing protocols • device and network independence• smart endpoints• service-oriented network functions

Openwave Systems Internet Standards Based Mobile Messaging

How Do We Fill the Gaps

Notification

• Some proposals exist, none seem to completely fit the bill

• Ideal solution should be applicable to all forms of messaging and content types

• LEMONADE needs to work on notification solution

Content Adaptation• Alternatives

1. Smart client analyzes content and selectively requests adaptation and/or download. eg: IMAP “CHANNEL http:” performs content adaptation based on HTTP Accept and/or USERAGENT

2. Capabilities exchange and “automatic” network based adaptation

Presentation Languages

• Use SMIL/XHTML/XML for both mobile and wireline clients

User Configurable Filters

• Use SIEVE (RFC 3028)

• Configuration of filters from clients is outside scope of LEMONADE

Openwave Systems Internet Standards Based Mobile Messaging

How Do We Fill the Gaps (continued)

Payload compression• Use IMAP Binary to avoid base64 expansion• compression best handled at network layers

Forward Without Download• SMTP or IMAP APPEND “Outbox” with IMAP URL in MIME part:

Content-type: Message/External-body,access-type=URL; URL=“IMAP: …”

Streamlined Submission and Retrieval

• Proposal made in 3GPP2:

X.P0016-311 MMS MM1 using M-IMAP

• Features:

• Manage submissions & retrievals over one connection to one server

• Basically IMAP with these enhancements:

• Pipelining (avoiding unnecessary transactions and RTT latencies)

• Brevity (omission of unneeded response text)

• DELIVER extension command (for submission & forwarding)

Openwave Systems Internet Standards Based Mobile Messaging

Proposal for Internet Standards Based Mobile Messaging

MobileClient

SMTP/IMAP4Server

MobileClient

(1)Submit msg

(SMTP)

(2)Notification

(???)

(3)Retrieval request

(IMAP)

(4)Retrieval request

(IMAP)

Feature Suggested Protocol

Submission (1) SMTP or IMAP APPEND “Outbox”

Notification (2) push delivery + URI

Retrieval (3) (4) IMAP FETCH [BINARY] or IMAP Channel:http

Forwarding SMTP or IMAP APPEND “Outbox” w/IMAP URL

Addressing RFC2822, E.164 & RFC2916

Notification filters SIEVE RFC3028

Content adaptation

IMAP Channel http:

Openwave Systems Internet Standards Based Mobile Messaging

Conclusion

• Internet Messaging Protocols should be improved to fulfill mobile messaging requirements.

• Why?– Avoid creating new messaging protocols and reuse existing

enhanced messaging protocols with enhancements– Simplify Internet email interworking and avoid messaging

gateways– Reinforce basic IP end-to-end application architecture

• Changes are required to “mobilize” Internet email – Push based notification– Content adaptation– Forwarding (without downloading)– Presentation language

This presentation proposes potential solutions that LEMONADE should consider