Resolution core switch optical port-level connection mode and type

The port of the core switch is mainly of the optical fiber type, but the price of the optical fiber port of the switch is very expensive. You must note that the optical fiber port of the switch is not stacked and can only be used for Cascade. Analyzes the connection methods and basic types of the optical fiber ports of the vswitch. Cascade uses both common ports and special MDI-II ports. A straight-through cable should be used when the two ports that are cascaded are normal ports (MDI-X) ports and MDI-II ports, respectively. Cross-cable should be used when both ports of mutual cascade are common ports, that is, MDI-X) or both are MDI-II ports.

Whether it is 10Base-T Ethernet, 100Base-TX fast Ethernet, or 1000Base-T Gigabit Ethernet, the length of the cable used by the cascade switch can reach 100 meters, which is exactly the same length as that between the core switch and the computer. Therefore, in addition to expanding the number of ports, cascade is also used to quickly extend the network diameter. When four vswitches are uplinked, the network span can reach 500 meters. This distance is enough for a small network in the same building!

Uplink ports are now available, except for more and more Cisco switches. This simplifies the connection between core switches. Uplink port is a dedicated port used to connect to other vswitches. You can use a straight-through jumper to connect the port to any port other than the Uplink port of another vswitch.

The connection method is the same as that between the computer and the switch. Note that some brands of vswitches such as 3Com use a common port and Uplink port, and use an MDI/MDI-X switch) to switch between the two types. Use the Uplink port to connect to a vswitch through the express connect.

Use common port Cascade

If the core switch does not provide a dedicated cascade port Uplink port), you can only use a jumper to connect the common ports of the two switches and expand the number of Network Ports. When using a common port to connect to a vswitch, you must use a cross line instead of a direct line. Use a crossover line to pass through a common port cascade switch.

Cascade of vswitch Optical Fiber ports

Because the price of the fiber-optic port of the switch is still very expensive, the fiber-optic is mainly used for connection between the core switch and the backbone switch, or for cascade between the backbone switch. Note that the optical fiber ports of the vswitch are not stacked and can only be used for Cascade.

Optical jumper crossover

Each vswitch has two fiber ports, one for one request. Of course, the optical fiber jumper must also be two; otherwise, communication between ports fails. When the core switch is cascade through the optical fiber port of the core switch, the two ends of the optical fiber jumper must be sent and received. When one end is "received", the other end is "sent ".

Similarly, when one end is connected with "sending", the other end is connected with "receiving ". The CiscoGBIC Optical Fiber Module is marked with a sending and receiving sign. The arrows on the left side indicate "receiving", and the arrows on the right side indicate "sending ". If both ends of the optical jumper are connected to "receive" or "send", the LED light on the port is not on, indicating that the connection is failed. The LED indicator turns green only when the optical fiber port of the vswitch is successfully connected.

Cascade of vswitch Optical Fiber ports

Similarly, when the backbone switch is connected to the core switch, the optical fiber receiving and receiving ports must also be cross-connected. Connection between the core switch and the backbone switch

Optical jumper and switch optical port type

Jumper cables are divided into single-mode optical fiber and multi-mode optical fiber. The optical fiber port and jumper of the switch must be consistent with the optical fiber type used in the Integrated Wiring. That is to say, if the multi-mode optical fiber is used in the Integrated Wiring, the optical fiber interface of a vswitch must comply with the 1000Base-SX standard and multimode optical fiber jumper. If the single-mode optical fiber is used in integrated wiring, the optical fiber interface of the vswitch must comply with the 1000Base-LX/LH standard, the Single-Mode Optical Fiber jumper must also be used.

Note that Multimode Optical Fiber has two types: 62.5/125 μM and 50/125 μM. Although the optical fiber ports of the vswitch are identical and both adopt the 1000Base-SX standard, the core diameter of the optical fiber jumper must be exactly the same as that of the optical fiber cable.

Otherwise, the connectivity will fail. In addition, the fiber ports of the vswitch must be of the same type, both of which are fiber ports of a Multimode switch or fiber ports of a single-mode switch. One end is the fiber port of a Multimode switch, and the other end is the fiber port of a single-mode switch, which cannot be connected together.

Transmission Rate and duplex mode

Unlike 1000Base-T, 1000Base-SX, 1000Base-LX/LH, and 1000Base-ZX do not support self-adaptation. Ports of different speed and duplex working modes cannot connect and communicate. Therefore, each fiber port must have the same transmission rate and duplex working mode. Therefore, you cannot connect a Mbps fiber port to a Mbps fiber port, the full-duplex mode fiber port cannot be connected with the half-duplex mode core switch fiber port. Otherwise, the connectivity will fail.