Novell NETWARE 6, Руководство пользователя

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Internetwork Packet Exchange
Internetwork Packet Exchange
103-000176-001
August 29, 2001
Novell Confidential
Manual 99a
38
July 17, 2001
3. The sending workstation places the node address of the router that
responded to the RIP request in the Destination Address field of the MAC
header.
4. The sending workstation places its own node address in the Source
Address field of the MAC header.
5. The sending workstation sends the packet.
When a Router Receives an IPX Packet
When a router receives an IPX packet, it performs the following tasks:
1. The router checks the Transport Control field of the IPX packet header.
A RIP router discards the packet if the value in this field is greater than
16.
An NLSP router discards the packet if the value in this field is greater than
the value of the Hop Count Limit parameter.
2. The router checks the IPX header Packet Type field.
Note that if the packet type is 20 (0x14, NetBIOS), the packet is handled
as follows:
a. The router examines the Transport Control field of the IPX header. If
this value is 8 or greater, the router discards the packet. (Propagation
of a NetBIOS packet is limited to eight networks.)
b. The router compares each network number entry in the packet to the
network number of the segment on which the router received the
packet.
If the router finds a match, it discards the packet to prevent multiple
traversals of the same network segment. If the router finds no match,
it performs the next step.
c. The router places the address of the network segment from which the
packet arrived in the next available Network Number field.
d. The router increments the Transport Control field of the IPX header
and broadcasts the packet to all directly connected network segments
that are not represented in the Network Number fields.
3. The router checks the IPX header Destination Address fields—network,
node, and socket numbers—to determine how to route the packet.