NIM WITH MULTIMODE 4 PAIR/G.SHDSL EFM AND ATM IN

The Cisco 4000 Series Integrated Services Routers Network Interface Module (NIM) supports single-port Cisco Multimode Four-Pair G.SHDSL-based WAN connectivity using both 802.3ah Ethernet in the first mile (EFM) and ATM modes. This NIM is used in modular routers that are deployed in Small and Medium-sized Businesses (SMBs) and enterprise branch offices.

Designed to deliver high-speed Ethernet services over Symmetrical High-speed DSL (SHDSL) access, the multimode G.SHDSL NIM (Figure 1) offers symmetric data rates over one to four pairs of copper wire and supports both EFM and ATM modes. To achieve higher bandwidths, bonding of multiple pairs (4-wire, m-pair, inverse multiplexing over EFM bonding) is supported.

In EFM mode, the multimode G.SHDSL NIM allows bonding, as defined by IEEE 802.3ah, and is typically used in scenarios where individual links are aggregated using the 802.3ah loop aggregation. Depending on the number of wire pairs in service, the maximum data rate is 61.4 Mbps, with each line supporting up to 15 Mbps with 128-TCPAM. The NIM complies with the 2BASE-TL standard, which is based on the IEEE 802.3ah EFM standard. The 2BASE-TL standard uses the technology standard defined in ITU recommendation G.991.2 (G.SHDSL.).

In ATM mode, the multimode G.SHDSL NIM allows bonding of multiple pairs up to four pairs (8-wire) with increased bandwidth by using data interleaving and m-pair mode. In m-pair mode, the multimode four-pair G.SHDSL NIM offers data rates up to 5.7 Mbps per pair and up to 22.7 Mbps over four pairs. (See Table 2 for the data rates supported by the multimode four-pair G.SHDSL NIM (NIM-4SHDSL-EA) under different modes.)

The multimode four-pair G.SHDSL NIM cost-effectively allows service providers and enterprise customers to deliver Ethernet services to sites with no access to fiber by using bonded copper pairs with symmetrical bandwidth. These rates cover applications traditionally served by High-data-rate DSL (HDSL), Single-line DSL (SDSL), T1, E1, and services beyond E1.

The multimode four-pair G.SHDSL NIM, together with the ISR 4000 series router, provides businesses the necessary bandwidth for critical traffic such as voice and videoconferencing and enables customers to save money by integrating voice and data traffic on the same WAN link. Service providers can increase subscriber revenue by bundling services and offering differentiated service levels through Service-Level Agreements (SLAs).