RFC1582 - Extensions to RIP to Support Demand Circuits( 十 )

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Followed by up to 50 routing entries (each 8 octets)
0 1 2 3 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
network number (4)
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number of hops (2)number of ticks (2)
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.
.
The format of a Netware RIP datagram in octets, with each tick
mark representing one bit. All fields are in network order.
The four octets: sequence number (2), fragment number (1) and
number of fragments (1) are not present in the original RIP
specification. They are only present if operation takes the
values 7 or 8.
Figure 3. Netware Routing Information Protocol packet format
TRIGGERED REQUEST (6)
A request for the responding system to send all of its
routing database.
Only the first 2 octets of the packet format shown in
figure 3 are sent, since all routing information is
implied by this request type.
TRIGGERED RESPONSE (7)
A message containing all of the sender"s routing
database, excluding those entries learned from the
interface to which the routing information is being
sent.
This message may be sent in response to a triggered
request, or it may be an update message resulting
from a change in the routing database.
A triggered response message MUST be sent in response
to a triggered request message even if there are no
routes to propagate. This would be the case for a
host which had a WAN interface only, but which wished
to run the triggered update protocol.
TRIGGERED ACKNOWLEDGEMENT (8)
A message sent in response to every triggered
response packet received.
Only the first 6 octets of the packet format shown in
figure 3 are sent.
SEQUENCE NUMBER
This is a new field inserted if operation takes the
values 7 or 8.
The sequence number MUST be incremented every time
updated information is sent out on a WAN. The sequence
number wraps round at 65535.
When a triggered acknowledgement is sent the sequence
number is set to the same value as the triggered response
packet being acknowledged.
The sequence number MUST be identical over fragments. If
a fragment is retransmitted the sequence number MUST not
change.
FRAGMENT NUMBER
The fragment number is one for the first fragment of a
routing update, and is incremented for each subsequent
fragment. A fragment can contain up to 50 routing entries.
When a triggered acknowledgement is sent the fragment
number is set to the same value as the triggered response
packet being acknowledged.
NUMBER OF FRAGMENTS
In a triggered response packet this indicates the number
of packets required to complete the routing update.
This field has no relevance for triggered acknowledgement
packets so should be set to zero.
For triggered response packets the rest of the datagram contains a
list of networks, with information about each. Each entry in this
list contains a destination network, and the number of hops and
number of ticks for each.
The maximum datagram size is 406 octets, excluding the IPX header (a
further 30 octets).
6. Netware Service Advertising Protocol
This section should be read in conjunction with references [3], since
it only describes differences from the specification.
Netware [3] also supports a mechanism that allows servers on an
internetwork to advertise their services by name and type using the
Service Advertising Protocol (SAP) which runs over the Internetwork