Cisco TelePresence Server 7010, Руководство по установке и обслуживанию оборудования

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Preparing for Installation 2-29
Preparing Network Connections
Token Ring Cables and Connectors
The Token Ring ports on the TRIP are DB-9 (PC type) receptacles that require Type 1 or Type 3 lobe
cables. Type 1 lobe cables use shielded twisted pair cable and terminate at the network end with a
large MAU plug. (See Figure 2-17.) Type 3 lobe cables use either shielded or unshielded twisted pair
(UTP) cable and terminate at the network end with an RJ-11 plug. (See Figure 2-18.) The TRIP end
of both cable types is a DB-9 plug.
Figure 2-17 Token Ring Type 1 Lobe Cable Connectors, DB-9 and MAU Types
Figure 2-18 Token Ring Type 3 Lobe Cable Connectors, DB-9 and RJ-11 Types
Token Ring Physical Connections
The term Token Ring refers to both IBM’s Token Ring Network, which IBM developed in the 1970s,
and to IEEE 802.5 networks. The IEEE 802.5 specification was modeled after, and still closely
shadows, IBM’s network. The two types are compatible, although the specifications differ slightly.
The IBM Token Ring specifies a star topology, with all end stations connected through a device
called a multistation access unit (MSAU). IEEE 802.5 does not specify any topology, although most
implementations are based on a star configuration with end stations attached to a device called a
media access unit (MAU). Also, IBM Token Ring specifies twisted pair cabling, whereas IEEE
802.5 does not specify media type. Most Token Ring networks use shielded twisted pair cabling;
however, some networks that operate at 4 Mbps use unshielded twisted pair cable. Table 2-14 shows
a comparison of the two types.
H2056
TRIP end
MSAU or
MAU end
H2055
TRIP end
MAU end