IPX/SPX

1
IPX/SPX

• Novell Internetwork Packet Exchange (IPX) has
  been around since 1980s.
• Novell Netware was the most popular network
  operating system in 1980s.
• Currently, Novell uses TCP/IP as default network
  protocol.
• Why should we learn about IPX/SPX?

2
IPX/SPX Protocol Stack
3
IPX/SPX Protocol Stack

• Internetwork Packet Exchange (IPX)
• Connectionless, predominantly layer 3 protocol
• Responsible for finding the best path through a
  multipath IPX network
• Sequenced Packet Exchange (SPX)
• Connection-oriented layer 4 protocol
• Provides guaranteed delivery services for the
  connectionless IPX
• Service Advertisement Protocol (SAP)
• Operates at layers 5, 6, and 7
• Advertises services running on IPX/SPX servers

4
IPX/SPX Protocol Stack

• NetWare Core Protocol (NCP)
• Functions at layers 4, 5, 6, and 7 of the OSI
  model
• Facilitates client/server interaction on a
  NetWare network
• Routing Information Protocol (RIP)
• Distance-vector protocol built into the IPX/SPX
  protocol stack
• Operates at layer 3
• Uses ticks and hop counts as metrics
• NetWare Link Services Protocol (NLSP)
• Link state routing protocol designed by Novell
• Functions at layer 3

5
IPX/SPX Addressing

• 80-bit (10 bytes) addresses consisting of a
  32-bit (4 bytes) network portion and a 48-bit
  node portion
• The network administrator arbitrarily assigns the
  network portion
• No subnetting! No address classes!
• MAC address of the node makes up the node portion
  of the address
• Addresses normally appear in hexadecimal format
• 0000.7C80.0000.8609.33e9
• What is good about using MAC addresses?

6
Communication

• Client-Server
• Novell Netware follows a strict client-server
  model.
• Every Netware server builds a service
  advertisement table comprising all the network
  resources that it is aware of.
• Clients use Get Nearest Server (GNS) request to
  locate servers.
• Server-Server
• Servers use SAP and RIP.

7
Service Advertisement Protocol (SAP)

• SAP advertisements on an IPX/SPX network allow
  servers to advertise running services to
  network clients
• NetWare servers take SAP broadcasts and build SAP
  tables.

8
Encapsulation
9
Lab