HP 200 Series Services And Applications page 246

Shining a Light on FDDI
Internetworking with HP Routers
Internetworking with HP Routers
HP's FDDI link interfaces are compliant with the following ANSI X3T9.5
standards:
Physical Medium Dependent (PMD)
Physical Layer Protocol (PHY)
Media Access Control (MAC)
System Management (SMT)
They also comply with RFC 1188, which specifies transmission of IP data-
grams over FDDI media, and with IEEE 802.1 Parts D & H.
Physically, they provide a single MAC connection and support both Class A
and Class B attachments to FDDI media. A Class A attachment requires two
physical connectors and provides connectivity between a Dual Attachment
Station (DAS) and the FDDI primary and secondary rings. A Class B attach-
ment uses a single physical connector and provides connectivity between a
Single Attachment Station (SAS) and the FDDI primary ring or an FDDI
concentrator. HP's FDDI link interfaces only support multimode 50-micron
or 62.5-micron graded-index fiber-optic cable.
FDDI Routing
Since routers are media-independent, they encapsulate packets to conform
to the media type in use. RFC 1188 specifies 802.2 LLC with SNAP (subnet-
work access protocol) when routing TCP/IP traffic over FDDI media.
RFC-1188-conforming routers provide IP routing between source and
destination end systems on Ethernet or 802.3 LANs across an FDDI
backbone, as well as to destination systems directly connected to the
backbone.
Other routable protocols are translated on the FDDI ring according to rules
defined by RFC 1188 and IEEE 802.1 bridge standards. Adherence to such
rules allow interoperability between multiprotocol routers and translating
bridges that may be attached to the same FDDI ring. The protocols
supported on FDDI include:
IP
Novell IPX
Appletalk Phase 2
DECnet Phase IV
Xerox XNS
HP Probe
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