Specifications

Chapter 1. Router Concepts 25
Interoperability Between the Router and Other Equipment
The router uses industry-wide standards to ensure compatibility with routers and equipment from other vendors.
To interoperate, the router supports standard protocols on the physical level, data link level for frame type or
encapsulation method, and network level. For two systems to communicate directly, they must use the same
protocol at each level. Most protocols do not support negotiable options, except for PPP.
The physical protocol level includes hardware and electrical signaling characteristics. This support is provided by
the router Ethernet and modem hardware interfaces.
The router supports both ATM (Asynchronous Transfer Mode) and Frame Relay transmission. ATM transports
fixed-length cells; Frame Relay transports variable-length packets.
The data-link protocol level defines the transmission of data packets between two systems over the LAN or WAN
physical link. The frame type or encapsulation method defines a way to run multiple network-level protocols over
a single LAN or WAN link. The router supports the following WAN encapsulations:
¥ PPP (VC multiplexing)
¥ PPP (LLC multiplexing)
¥ PPPoE (PPP over Ethernet)
¥ RFC 1483 (for ATM)
¥ RFC 1483 with MAC encapsulated routing (for ATM)
¥ FRF8 (for ATM)
¥ RFC 1490 (for Frame Relay)
¥ RFC 1490 with MAC encapsulated routing (for Frame Relay)
Protocol Conformance
The router conforms to RFCs designed to address performance, authentication, and multi-protocol encapsulation.
The following RFCs are supported:
¥ RFC 1058 Routing Information Protocol (RIP)
¥ RFC 1144 Compressing TCP/IP headers (Van Jacobson)
¥ RFC 1220 Bridging Control Protocol (BNCP)
¥ RFC 1332 IP Control Protocol (IPCP)
¥ RFC 1334 Password Authentication Protocol and Challenge Handshake Authentication Protocol (PAP/
CHAP)
¥ RFC 1389 RIP2
¥ RFC 1483 Multiprotocol Encapsulation over ATM Adaptation Layer 5
¥ RFC 1490 Multiprotocol Interconnect over Frame Relay
¥ RFC 1542 DHCP Relay Agent
¥ RFC 1552 Novell IPX Control Protocol (IPXCP)
¥ RFC 1577 Classical IP and ARP over ATM
¥ RFC 1631 Network Renumbering
¥ RFC 1661 Point-to-Point Protocol (PPP)
¥ RFC 1723 RIP Version 2