Mobile Backhaul

5.5 Leased Line Services for Mobile Backhaul

Leased Line Services are one alternative for the Mobile Operator to implement the transport connections in the MBH network. Conventional TDM leased lines (i.e. PDH E1s and T1s) have been used right from the beginning of first Mobile Networks (2G, GSM), but the transition to packet based technologies and higher MBH bit rates has led to TDM leased lines gradually being superseded by Ethernet services. Based on the forecast of Figure 2.10 (packet-based technologies in MBH networks) and by assuming that the majority of wire-line connections and ca. 5--10% of wireless (i.e. MWR-based) are leased, we may conclude that more than 50% of all MBH connections today, and in the near future, are leased.

There are several leasing cases as shown in Figure 5.14 below. If the leasing provider is incumbent and connection is TDM, i.e., E1/T1, it is often quite easy to lease the whole connection towards the mobile core starting from a BTS site. The access link can use DSL, fiber or MWR (case 2 in Figure 5.14). An independent transport provider can also offer leasing services starting from the BTS site, but they have to hire the copper line from the incumbent provider's access network. These non-incumbent providers also have access fiber, but often with a very limited coverage compared to the incumbent providers. A mobile operator may also build a partially owned/partial leased network, for example such that he only owns access and leases the rest (cases ...