User`s guide

Customer Domain Features
2-2
8000-A2-GB21-10
June 1997
The following are the maximum upstream and downstream data rates with
standard #26 AWG wiring, and 24 ISDN disturbers in the same 25-pair binder
group:
 Maximum upstream data rate: 1088 kbps (remote access from the customer
premises to the CO up to a distance of 8,300 feet)
 Maximum downstream data rate: 2560 kbps (remote access from the
customer premises to the CO up to a distance of 12,300 feet)
For a complete listing of the DSL card data rates, see Appendix C,
Data Rates , of
the appropriate HotWire DSLAM Installation Guide. For information on how to set
the line speed, see Chapter 6,
DSL Card Configuration , of the HotWire Digital
Subscriber Line Access Multiplexer (DSLAM) User’s Guide
.
Protocols
The HotWire DSLAM and HotWire 5446 RTU forward IP packets between the
end-user system and the Network Service Provider using the following protocols:
 Point-to-Point Protocol/High-level Data Link Control (PPP/HDLC)
Packets transmitted over DSL ports are encapsulated in PPP/HDLC.
 MAC
Packets transmitted over LAN ports are encapsulated in IEEE 802.3 MAC.
 IP
IP packets arriving over the DSL interface are IP forwarded to the LAN
interface. IP packets arriving over the LAN interface are IP forwarded to the
appropriate DSL interface.
NOTE:
Directed broadcasts (also referred to as subnet broadcasts — all
1s (ones) in the host field) are forwarded upstream, but are not forwarded
downstream.
Also, multicasting is not supported.
 Internet Control Management Protocol (ICMP)
In general, ICMP is supported. It should be noted, however, that the options
field is not reflected back if the HotWire DSLAM is the destination address
(i.e., the options field is stripped from the packet when the HotWire DSLAM
receives the data and then returns the packet without the options field). The
HotWire DSLAM does, however, pass the packet with the options field to the
next-hop if the DSLAM is not specified as the destination address.