Serving area interface

The Cross Connection Cabinet ( CCC ) is an approximately one meter high passive cabinet for cable distribution lines within a local telephone network, the main cable with branch cables connects.

Background

The cable branch box is connected to the main distributor of the local exchange on the so-called main cable and the branch cables carrying, by the surrounding buildings are connected to the telephone network. In Germany there are about 300,000 street cabinets, which are mostly on the roadside. These are today's most connected through main cable consisting of twisted copper wires to the nearest main distribution. Following the expansion of the data transmission rate in the access network cable distributors are increasingly connected to the main distribution directly over fiber optic cable.

Depending on requirements, the individual cable cores of the main and branch cable via switch wires are connected to each other in the street cabinet ( " ranks "). Currently, however, solutions are developed to automate the manual maneuvering with the help of remote controlled switching matrices.

The use of street cabinets is not limited to the public telephone network, even in large corporate campuses (for example in lime plants or stages ) cable splitter can be used.

Method of construction

If in the Kabelverzweigergehäusen active technology (eg amplifier of the broadband network ) installed, this can be due to the enclosed design lead to heat problems. Remedy in this case base with ventilation slots or a passive air roof, which dissipate heat of active network technology.

Outdoor DSLAM

Villages where no DSL or very low broadband data transmission rates are possible, be equipped with a sufficient demand by outdoor DSLAM. For this it is necessary to bind these sites with fiber optic cables that need to be re-laid mostly. The outdoor DSLAM are smaller than the indoor versions, but use the same connection modules ( line cards ).

What DSLAM variant is used is decided by expanding the local network.

The German Telekom is currently building from the street cabinet by a larger cabinet is placed over or next to (or in the vicinity of ) the street cabinet to install an outdoor DSLAM can connected via fiber to the local exchange. These are also known as multi-function case ( MFG). This makes it possible to provide participants with VDSL connections that can have a data transfer rate of 100 Mbit / s and more (initially only connections with up to 50 Mbit / s, are marketed ). The VDSL implementation gets installed in street cabinets. VDSL is currently in 50 local networks available (as of 07 /2009). More are planned.

For OPAL expansion areas there are special outdoor DSLAM, because the OPAL units can also be connected using fiber to the exchange, but they only transfer the frequency range up to ~ 120 kHz ( ISDN bandwidth) in the glass network. About this technology can also areas that are connected via a OPAL pipeline grid, are supplied with DSL. For outdoor DSLAMs are also installed and the street cabinet retrofitted with it.

In some areas, the DSLAM will convert the analog signals of telephone calls to VoIP, so that the connection can be saved to an exchange. Their task was then taken over by the DSLAM and the downstream of it technology for routing IP packets.

Trivia

• Often, are confused because of its resemblance to the so-called post Kabelverzweigerkästen storage or depot boxes of Deutsche Post AG.