Introduction E-1
Appendix EIR-IP Interface Module

E.1 Introduction

Introduction IR-IP is a high-performance, miniature IP router based on RAD's unique IP
router chip, the ChipRouter.
IR-IP works by taking each Ethernet frame from the LAN and determining
whether the IP packet is destined for the IP net on the Ethernet LAN. If not,
IR-IP forwards the packet to the WAN link. IP packets received from the
WAN link are automatically forwarded to the LAN if the IP net matches.
IR-IP includes hardware filters which handle all filtering operations at wire
speed from both LAN-to-WAN and WAN-to-LAN, without dropping a single
packet. Filtering and forwarding are performed at the maximum rate of
35,000 and 30,000 frames per second (wire speed), respectively. The buffer
can hold 256 frames of maximum size of 1534 bytes and a throughput
latency of one frame.
IR-IP is available with 10BaseT (UTP) interface and is fully
IEEE 802.3/Ethernet v2 compliant. The IR-IP interface can also operate in full
duplex Ethernet applications.
HCD-E1 equipped with IR-IP interface module can be used as a Frame
Relay Access Device (FRAD) with an integral IP router. RFC 1490 is
supported for a single DLCI on the WAN link. Detection of the DLCI and
the maintenance protocol is performed automatically. This allows the IR-IP
to be used as the termination unit of IP services over Frame Relay at the
customer premises, opposite a Frame Relay switch in the backbone.
Alternatively, Point-to-Point Protocol (PPP) can be run on the WAN link with
automatic negotiation on power-up, as well as support for PAP and CHAP
authentication. With this feature, IR-IP can operate opposite any PPP
compliant access server or backbone router.
IR-IP supports HDLC, which is especially important for broadcast and
multicast applications where bandwidth overhead is critical.
IR-IP supports IP multicast at wire speed, making it suitable for any multicast
environment including high speed downstream environments, such as
satellite and xDSL. Users on the LAN who register with IR-IP for an IP
multicast group using the IGMP protocol filter IP multicast packets at wire
speed.
Management and advanced configuration are performed via Telnet.