Cisco ONS 15454 SDH - Available Circuit Sizes for E-Series Modes; Port-Mapped (Linear Mapper)

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Cisco ONS 15454 and Cisco ONS 15454 SDH Ethernet Card Software Feature and Configuration Guide, R8.0
Chapter 23 E-Series and G-Series Ethernet Operation
E-Series Modes
Port-Mapped (Linear Mapper)
Port-mapped mode, also referred to as linear mapper, configures the E-Series card to map a specific
E-Series Ethernet port to one of the card’s specific STS/VC circuits (Figure 23-13). Port-mapped mode
ensures that Layer 1 transport has low latency for unicast, multicast, and mixed traffic. Ethernet and Fast
Ethernet on the E100T-G or E10/100-4 card operate at line-rate speed. Gigabit Ethernet transport is
limited to a maximum of 600 Mbps because the E1000-2-G card has a maximum bandwidth of
STS-12c/VC4-4c. Ethernet frame sizes up to 1522 bytes are also supported, which allow transport of
IEEE 802.1Q tagged frames. The larger maximum frame size of Q-in-Q frames (IEEE 802.1Q in IEEE
802.1Q wrapped frames) is not supported.
Figure 23-13 E-Series Mapping Ethernet Ports to STS/VC Circuits
Port-mapped mode disables Layer 2 functions supported by the E-Series in single-card and multicard
mode, including STP, VLANs, and MAC address learning. It significantly reduces the service-affecting
time for cross-connect and TCC2/TCC2P card switches.
Port-mapped mode does not support VLANs in the same manner as multicard and single-card mode. The
ports of E-Series cards in multicard and single-card mode can join specific VLANs. E-Series cards in
port-mapped mode do not have this Layer 2 capability and only transparently transport external VLANs
over the mapped connection between ports. An E-Series card in port-mapped mode does not inspect the
tag of the transported VLAN, so a VLAN range of 1 through 4096 can be transported in port-mapped
mode.
Port-mapped mode does not perform any inspection or validation of the Ethernet frame header. The
Ethernet CRC is validated, and any frame with an invalid Ethernet CRC is discarded.
Port-mapped mode also allows the creation of STS/VC circuits between any two E-Series cards,
including the E100T-G and E1000-2-G. Port-mapped mode does not allow ONS 15454 E-Series cards
to connect to the ML-Series or G-Series cards.
Available Circuit Sizes For E-Series Modes
Table 23-1 shows the circuit sizes available for E-Series modes on the ONS 15454 and ONS 15454 SDH.
SONET/SDH
ONS Node
ONS Node
1:1 Ethernet port to STS/VC circuit mapping
83497