Flexibility in Trunk Microwave Deployment and Expansion

The RTN 6900 adopts standalone branching units (BUs) and can be flexibly deployed for network expansion and evolution.

• Using standalone BUs simplifies the installation process in that an RFU can be easily mounted onto a BU. The RFU and IDU are connected by using the IF cable.
• Microwave capacity upgrade is available. Microwave links can be easily upgraded from 4+0 to 8+0/12+0/16+0 through BU cascading.
• When multi-band BUs are used, each BU supports a maximum of 8+0 XPIC links, featuring high integration.
• Air-interface links are service-irrelevant. By adding or replacing service interface boards, SDH services can be smoothly upgraded to Ethernet services and co-transmission of both services can be achieved.

Highly Reliable Long-Haul Microwave Transmission

• The RTN 6900 supports space diversity (SD) to counteract multipath fading caused by long-distance transmission or seas/lakes.
• The RTN 6900 provides comprehensive equipment-level, link-level, and network-level protection schemes to build a highly reliable network.

Seamlessly Integrated Networking Technologies

• The RTN 6900 is capable of directly interconnecting with RTN 900 series short-haul products through air interfaces to implement long-haul transmission of aggregated services.
• The RTN 6900 provides 25GE ports to form 25GE ring networks or to serve as a supplement to optical fiber networks.

IP Microwave Classification

IP microwave can transmit packet services (Native Ethernet services or PWE3 packet services) and supports adaptive modulation (AM).

There are two typical types of IP microwave: Hybrid microwave and Packet microwave.

• Hybrid microwave: Native TDM services and Native Ethernet services can be transmitted concurrently through air interfaces.
• Packet microwave: TDM services and Ethernet services are transmitted through air interfaces after undergoing PWE3 encapsulation.

The RTN 6900 supports Integrated IP microwave where Hybrid microwave and Packet microwave are compatible and can concurrently transmit multiple types of services over air interfaces.

Integrated IP microwave

To achieve flexible transmission of TDM services and packet services over Integrated IP microwave, dual service planes are embedded in the RTN 6900: TDM service processing plane and packet service processing plane. TDM services and packet services can be flexibly transmitted over Integrated IP microwave, as shown in Figure 1-4.

• TDM service processing plane

  The TDM service processing plane performs cross-connection on the received TDM services (E1 services or STM-1 services) and transmits the services to microwave ports.

• Packet service processing plane

  The packet service processing plane processes and encapsulates the received multiple types of services (E1 services and Ethernet services) as required and transmits the services to microwave ports. Specifically,

  • For E1 services, it performs PWE3 emulation and then encapsulates them into MPLS packets for forwarding.
  • For Ethernet services, it performs Layer 2 switching and then forwards them as Native Ethernet services. Alternatively, it performs PWE3 emulation and encapsulates them into MPLS packets for forwarding, or it extracts IP packets from Ethernet, routes the packets through the VRFs of the packet plane, and then forwards the packets through RSVP-TE tunnels or LDP LSP.

Native TDM services, PWE3 packets, or Native Ethernet services are scheduled to microwave ports, mapped into microwave frames, and then transmitted on microwave links. Integrated IP microwave serves as Hybrid microwave when TDM services are scheduled to microwave ports over the TDM service plane and Ethernet services are scheduled as Native packets to microwave ports over the packet service plane. Integrated IP microwave serves as Packet microwave when TDM services and Ethernet services are encapsulated into MPLS/PWE3 packets on the packet service plane and then scheduled to microwave ports.