...T3 (DS3) E3 Analyzer software. This Pod is one of the smallest and lightest (weighing only 1.75 lbs) analyzer units on the market. The pod, when connected to a Notebook PC, is capable of capturing two full T3 (DS3) / E3 data streams, dropping and inserting T1 or E1, and Analysis of HDLC, ATM, Frame Relay, and PPP Protocols. T3 (DS3) or E3 can be channelized (structured) or unchannelized (unstructured).

In Channelized (Structured), a T3 (DS3) consists of 7 T2s (DS2) and each T2 consists of 4 T1s (DS1) for a total of 28 T1s, or 672 full duplex voice channels being provided. Similarly, an E3 consists of 4 E2s and each E2 consists of 4 E1s, thus a total of 16 E1s, or 480 full duplex voice channels are provided

In Unchannelized (Unstructured), T2s or T1s or E2s or E1s do not exist within T3 or E3. Instead, most of the capacity within 44.736 Mbps for T3 and 34.368 Mbps for E3 is used for data, with a small amount for overhead. With the advent of the Internet, T3 (DS3) and E3 can be used to transport not only data, but also packetized voice, and packetized video. Example protocols include Asynchronous Transfer Mode (ATM), PPP, HDLC, and Frame Relay. This is shown in the diagram below.

In the typical unchannelized circuit below, both ends will be set for scrambling, which can be vendor specific. If the scrambling is implemented in the router, then all vendor settings may be available. Subrate allows fractional bandwidth, i.e. less than the full 44.736 Mbps. Scrambling improves synchronization performance by randomizing repetitive patterns and long strings of zeros.