The Impact of the Radio Layer on Network Bandwidth Provisioning

Shows how the aggregated bit rate increases as we move into the network.
The highly asynchronous traffic loading is supported on a 2 Mbps ATM bearer
between the Node B and RNC and a 155 Mbps ATM bearer, or multiple bearers,
between the RNC and IP core. The job of the IP core is to process traffic, and (we
assume) a fair percentage of the traffic will be packetized. This is a packet-routed or,
more accurately, packet-queued network.
The radio physical layer is delivering individual users at user bit rates varying
between 15 kbps and 960 kbps. This is aggregated at the Node B onto multiple 2 Mbps
ATM wireline transport (copper access), which is aggregated via the RNC onto multiple
155 Mbps ATM (copper). This is aggregated onto 2.5, 10, or 40 Gbps copper and
optical fiber in the network core. The IP core may also need to manage highly asynchronous
traffic from wireline ADSL/VDSL modems (offering bit rates from 56 kbps to
40 Mbps).

As throughput increases, processing speed—and processor bandwidth—increases
(see Table 11.2). Routers must classify packets, and perform framing and traffic management.
If we have added packet-level security, the router must perform a deep
packet examination on the whole packet header to determine the security context.