Rfc877 Multiprotocol Encapsulation - Motorola 110502USM001 - Vanguard 60 Router User Manual

RFC877 Multiprotocol Encapsulation

Overview
Motorola's Version
of RFC887
RFC877 Limitations The following limitations apply to the use of RFC877:
Vanguard Routing Model
T0100-01, Revision B
RFC877 encapsulation specifies transporting of IP using NLPID (Network Layer
Protocol Identification) over X.25. The Vanguard Router rejects all RFC877 LCON
calls for other protocols.
When RFC877 encapsulation is selected, the IP datagram encapsulation is as
follows:
• First byte of the Call User Data (CUD) of Call Request will be "CC."
• The IP datagram is sent as part of X.25 data. There are no other headers or
trailers.
Motorola's version of RFC877 deviates from standard RFC877 where specification
of Router Maximum Transmission Unit (MTU) size is derived via WAN packet size
negotiation at the X.25 layer. Instead, the Vanguard Router supports a configurable
MTU size as specified in RFC1356, described below. Otherwise, the Motorola
version complies with all RFC877 requirements. Refer to the IP Interface
Configuration Table menu for more information on MTU size.
• Bridging and other routed protocols are not supported.
• Only one RFC877 incoming LCON call is supported. The incoming call is
assigned the lowest RFC877 LCON. Additional RFC877 calls are not
accepted.
Note: Any number (up to a maximum of 254) of outgoing RFC877 LCONs
can be set up.
• The RFC877 option of parallel SVCs between two routers is not supported.
When interoperating in a Cisco or Proteon network configured for Extended
LANView, you must turn off parallel SVC support on their routers.
• The Q-bit must not be set in the data packets. If the Q-bit is set, the call is
cleared.
WAN Adapter
2-9
Release 5.4