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3.1.2 Multiplexing
There are two conventions to identify what protocols the virtual circuit (VC) is
carrying. Be sure to use the multiplexing method required by your ISP.
The WebShare 111U Modem/Router supports followings tran sport methods:
VC-Based Multiplexing: In this case, by prior mutual agreement, each
protocol is assigned to a specific virtual circuit; for example, VC1 carries
IP, etc. VC-based multiplexing may be dominant in environments where
dynamic creation of large numbers of ATM VCs is fast and economical.
LLC-Based Multiplexing: In this case one VC carries multiple
protocols with protocol identifying information being contained in each
packet header. Despite the extra bandwidth and processing overhead,
this method may be advantageous if it is not practical to have a
separate VC for each carried protocol, for example, if charging heavily
depends on the number of simultaneous VCs.
3.1.3 VPI and VCI
Be sure to use the correct Virtual Path Identifier (VPI) and Virtual Channel Identifier
(VCI) numbers assigned to you. The valid range for the VPI is 0 to 255 and for the
VCI is 32 to 65535 (0 to 31 is reserved for local management of ATM traffic). Please
see the appendix for more information.
