NM Information Interworking. NM Information Transparently Transmitted by a Third-Party Equipment. The NM Information of the Third-Party Equipment is Transparently Transmitted, страница 2

Table 7-1 shows the features of this transmission mode.

Table 7-1 Features of the transparent transmission of NM information by the third-party equipment

Advantages	(1) Low cost: It does not require additional channels for data communication network (DCN). (2) Convenience: Where there is the optical fiber (including the microwave for SDH transmission), there is DCC. (3) The DCC is independent of service, so it is hardly influenced by the running of service.
Disadvantages	(1) It is limited by the third-party equipment. (2) It can only transparently transmit bytes D1–D12, E1, and E2 (3) No protection: If protection is required, you may use two transparent transmission channels of different trails.

7.1.2  The NM Information of the Third-Party Equipment is Transparently Transmitted

The NM information of the third-party equipment can be transmitted by bytes D4–D12 of the OptiX OSN 3500, as shown in Figure 7-2.

Figure 7-2 The NM information of the third-party equipment is transparently transmitted

The following three cases may exist.

n  The third-party equipment uses the D1–D3 bytes to carry its NM information. Then, at the network interconnecting point, the OptiX OSN 3500 maps the NM information in D1–D3 bytes of the third-party equipment into the D7–D9 bytes for transmission. On the other side of the network edge, the NM information in the D7–D9 bytes will be reverted into the D1–D3 bytes, thus fulfilling the transparent transmission of the NM information.

n  The third-party equipment uses the D4–D12 bytes for its NM information. Then, at the network interconnecting point, the OptiX OSN 3500 can also provide the transparent transmission of bytes D4–D12.

n  For orderwire bytes E1 and E2, the OptiX OSN 3500 at the network interconnecting point can use its D11 byte to carry the E1 byte, and use D12 byte to carry E2 byte of the third-party equipment.

Table 7-2 shows the features of this transmission mode.

Table 7-2 Features of the transparent transmission of NM information by the third-party equipment

Advantages	(1) Low cost: It does not require additional channels for DCN. (2) Convenience: Where there is the optical fiber (including the microwave for SDH transmission), there is DCC. (3) The DCC is independent of service, so it is hardly influenced by the running of service. (4) Free from the limitation of the third-party equipment.
Disadvantages	(1) It can only transparently transmit bytes D1–D12, E1 and E2. (2) No protection: If protection is required, you may use two transparent transmission channels of different trails.

7.2  IP Over DCC

The scheme of IP over DCC uses the network layer protocol for NM information transmission. It is required that the gateway NE, external DCN and element management system (EMS) all support internet protocol (IP), thus the network composed of the third-party equipment and that composed of equipment of Huawei (such as the OptiX OSN 3500) can form a DCN. Figure 7-3 shows the IP protocol stack of the OptiX OSN product.

Figure 7-3 The IP protocol stack of the OptiX OSN product

IP over DCC has two networking topologies:

n  The NM information of the OptiX OSN 3500 is transparently transmitted through IP over DCC by the third-party equipment, as shown in Figure 7-4.

n  The NM information of the third party is transparently transmitted through IP over DCC by the OptiX OSN 3500, as shown in Figure 7-5.

Figure 7-4 The NM information is transparently transmitted by the third-party equipment

Figure 7-5 The NM information of the third-party equipment is transparently transmitted

Table 7-3 shows the features of the NM information interworking in IP over DCC mode.

Table 7-3 Features of the NM information interworking in IP over DCC mode

Advantages

(1) Low cost: It does not require additional channels for DCN. (2) The IP over DCC mode is free from restriction of complex networking and can provide multiple transparent transmission paths, featuring great flexibility. (3) The IP over DCC mode is independent of the physical path, so it is easy to realize information interworking. (4) It supports automatic re-routing for protecting the NM information path.

Disadvantage

The related equipment is required to support the same network layer protocol.