Portfast

There are only 2 key switches that function with most if not all FTA receivers and regular(legacy) LNBs they are:
22khz switch, connects two LNBs to 1 receiver

DiSEqC 4×1 switch, connects up to four LNBs to a single receiver.

2 inputs are labeled 13v,0khz & 18v,0khz (remember the LNBFs internal switch), along with the other only two inputs are 13v,22khz & 18v,22khz. This enables both polarities from every single LNB to be inside the change at all times, so any with the four receiver can entry any polarity on either in the 2 LNBs.

These switches also are available in a 4×8 for approximately 8 receiver hook ups to two satellites.

DiSEqC-1 or two or three or four in your menu will trigger the DiSEqC change to swap to that numbered port, some receivers use A, B, C, D as opposed to 1, 2, 3, 4.

This “pulse” is only sent once, if the DiSEq alter is to far away from the receiver it can miss it and not alter ports, some times toggling back and forth between channels can make the alter happen, the pulse is repeated each and every time you alter channels, but moving the swap closer on the receiver can enhance its performance.

DiSEqC switches come in 2 main flavors, Committed(1.0) and Uncommitted(1.1), but also Committed 2-way(2.0) and UnCommitted 2-way(2.1).

Committed(1.0) switches are the most typical and are what come with the receivers.

These switches need FACTORY software in your FTA to function properly, 1.0 indicates your receiver can function Committed switches ONLY, 1.1 indicates it can operate Committed AND UnCommitted switches, 1.2 implies it can run Committed and UnCommitted plus DiSEqC motor controls.

2.0 could be the exact same as above, 2.0, 2.1, 2.2 but the receiver can also obtain facts back in the switch, 2.0 switches acquire the pulse command on the receiver, then transform ports, they then send back a confirmation towards the receiver, if a 2.0 receiver doesn’t receive the confirmation it will send the DiSEqC pulse once more and once again until the swap confirms it truly is about the correct port.

The CCNA/CCNP’s exam will ask of you to decide the purpose from the Portfast within the spanning-tree protocol.

Before we go into the detail for the intent and operation of the Portfast feature we have to recognize the switched network environment behaviour just before the introduction of portfast like a command..

There are no multiple receiver DiSEq switches for Legacy(regular) style LNBs

22khz switches and DiSEq switches can function well together, with one particular restriction, the 22khz move must arrive AFTER the DiSEq switch.

From the “BPDU Guard” article you will recall that the stability of the Root Bridge is of paramount importance inside operation and continual uninterrupted support of spanning-tree and that a transform within the position on the Root Bridge will result in service disruption around the network; a different significant factor to bear in mind is that’s it not just the changing from the position in the Root Bridge that could bring about network disruption but events including access switchports transitioning on/off line can create an unstable network.

When a port 1st goes on-line spanning-tree will treat it like it treats any other port and will cycle by way of the normal spanning-tree port roles, i.e. blocking, listening. Learning, forwarding. The port will transition to the forwarding state following 30secs.

If you decide that the information is helpful you might also want to be finding out about Tomcat Change Port.

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