Lucent Optical Management System (oms) Release
Data communication channels (DCC)
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- Điều hướng trang này:
- DCC channel selection The following DCC channels exist on an STM- n
- AITS and UITS supported
| Data communication channels (DCC)
The data communication channels (DCC) are part of the data communication network (DCN). The channels are used to exchange management data between the management system and the network elements. The channels are also used for communication between the different network elements (for example remote logins). The DCC connection is achieved by means of layer 2 protocol High Level Data Link Control (HDLC) Frame bridging (at the data link layer level). HDLC Frame bridging always applies to two ports (labelled TTP1 and TTP2); more than two ports (that is, broadcasting) is not supported. The DCC connection is implemented via Layer bridging. DCC channel selection The following DCC channels exist on an STM- n connection: • DCC bytes of the RSOH (bytes D1-D3) termed RS-DCC. • DCC bytes of the MSOH (bytes D4-D12) termed MS-DCC. LAPD protocol The LAPD protocol, which controls communication between the network elements, operates in either of the following modes: • Network side The LAPD is assigned as network. This mode complies with the standards and interoperates successfully with other LAPDs operating in user_side mode. • User side The LAPD is assigned as user. This mode complies with the standards and interoperates successfully with other LAPDs operating in network_side mode. Please note that the DCCs work according to the master/slave principle, that is the LAPD modes of two interconnected SDH ports must be set differently. A corresponding “user-network side failure” alarm will be generated if the LAPD mode is the same at both ends of a DCC. AITS and UITS supported Metropolis ® ADM (Universal shelf) network elements support the acknowledged information transfer service (AITS) and the unacknowledged information transfer service (UITS) as the basis for the LAPD or LinkID protocol with the UITS mode being the default mode of operation. AITS should only be used if required by other NE types. UITS is furthermore used for link protocol at the same time when AITS is chosen. Management communication setup concepts ................................................................................................................................................................................................................................... 3-12 tải về 2.06 Mb. Chia sẻ với bạn bè của bạn:
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