Networking in Networking in Windows 2000Windows 2000

NT Layered Network NT Layered Network ArchitectureArchitecture

Network Interface Card

Network Adapter Card Drivers

NDIS Interface Streams

Streams

Transport Protocols

Transport Driver Interface

NetBIOS driver

Redirectors Servers WinSock driver

1. Physical

2. Data Link

3. Network

MAC

LLC

4. Transport

5. Session

6. Presentation

7. Application

Kernel Mode

User Mode

Some basic Some basic conceptsconcepts

NDIS Interface: Network Driver Specification Interface, wraps NIC drivers and allow communication with multiple protocols, binds a NIC to a protocol.

Streams: multiple channels allowing broader bandwidth for data transfer, envelop the protocols.

Transport Driver Interface: allows software drivers (server, redirector, etc) to communicate with protocols.

Redirectors: software in WS that redirect network drives, printers requests to network I/O requests.

Servers: software that allows a device to accept requests from other devices.

Standard NT Standard NT protocolsprotocols

NetBEUI - NetBIOS Extended User Interface, “native” Windows protocol, not routable.

TCP/IP - implemented through WinSock, routable, supports SNMP, DHCP, WINS.

NWLink (IPX/SPX) - used to connect to Novell NetWare, just a protocol, not access.

DLC - Data Link Control, used to connect to IBM mainframes and HP printers directly connected to a network (server).

Network Resource Network Resource AccessAccess

UNC - Universal Naming Convention machine name: \\mname <= 15 digits share name: \sname <= 12 digits example: \\AL200\HP6 sharing: net share public= c:\temp using: net use lpt2: \\Al200\public also graphical

Master Browsers - allow to see what resources are available Win NT/2000 use Network Neighborhood

MUP driver - Multiple Universal Naming Convention Provider

Workgroup and Workgroup and DomainDomain

Peer to Peer a machine joins a group by declaring (Control Panel) group names <= 15 digits peer-to-peer and guest, should not be allowed shares require username and password

Concept: a group of NT/2000 machines that share “a security server” - the domain controller Windows 9x may join by selecting as workgroup the

domain name user name <= 20 digits, password <= 14 digits users have permissions and rights in groups SAM - Security Account Manager, keep user information Naming a machine and joining a domain: right-click on

MyComputer, select properties, Network identification and properties.

AddressesAddresses Ethernet address (MAC address )

48-bit unique addresses hard wired in NICs (280 trillion)

12 hex numbers, e.g. 00-A0-C9-9F-00-07 first three identify company, Intel in the

example how to see: System Information,

Network Adapter IP address (number)

32-bit value, not hard coded (4 billion), assigned manually or by DHCP

four dotted quads, each quad a decimal from 0-255, corresponding to eight bits, e.g. UBMAIL IP address is 198.202.0.25

InternetingInterneting

Station A wants to send message to station D, but IP number is not in the same subnet -- no can do!

Sends the message to the default IP router -- default gateway

All stations belonging to the same subnet share the first three dotted quads.

204.52.128.67 and 204.52.128.147 are in the same subnet, while 198.202.0.25 is not.

A,B and C-Class NetworksA,B and C-Class Networks A-class networks

first 8 bits fixed, from 0-126 (only 127) very large companies like IBM, BBN, DEC,HP can assign 3 dotted quads - up to 16.7 million hosts

B-class networks first 16 bits fixed, first quad 128-191 and second 0-

255 (16,384) Medium-sized companies like Microsoft, Exxon can assign 2 dotted quads - up to 65,536 hosts

C-class networks first 24 bits fixed, first quad 192-223, second and

third 0-255 (2,097,152) can assign 1 dotted quad - up to 253 hosts, 0 is the

subnet address., 1 default router address, 255 broadcast address.

Sockets and WinSockSockets and WinSock Special addresses

Network address: first address in subnet (0) Router address: second address in subnet (1) Broadcast address: last address in subnet (255)

Sockets are the basic TCP requirement Socket address

IP address of the receiver Port number of the receiving program (80,21,23) Type of port TCP or UDP

WinSock is an adaptation of sockets to the PC part of the OS (Windows, Linux, etc.) an application programming interface

Setting static IP Setting static IP addressesaddresses

Go to Control Panel and select Network and Dial-up connections

In the first time select Make New Connection, local area network.

After the first time right-click on Local Area Connection and select properties.

In both cases you will see the properties dialog, which allows you to install/uninstall client, service or protocol.

Select the Internet Protocol and click on properties

Fill in IP number, Subnet Mask, Default Gateway, DNS

Use ping to test your setup. Dynamic IP addresses: use DHCP (Dynamic Host

Configuration Protocol), which requires a server in another machine.

How does DHCP work?How does DHCP work?

DHCPCLIENT

DHCPCLIENT

DHCPSERVER

DHCPDATABASE

MAC address

MAC address, IP#,lease time

DHCP discover

DHCP offer

IP#, lease time

IP scope

DHCP request

IP#, MAC address

IP#, lease time

DHCP ack

(1)

(2)

(0)

• Scope - a range of IP addresses• IP lease - the IP# is assigned temporarily• Reserved IP - servers are assigned fixed IP addresses