Protection types: What's different between them?

[tjcho]

When it comes to say "Protection Types", there are many types I could see:

1:1 mode

1+1 mode

1:m mode etc...

Could someone explain what they are?

Thanks in advance.

[tgimmel]

1:1) 1 for 1 on metallic, ie DS3, EC1 etc. One card is working and the other standby

1+1) 1 Plus 1 for optical, ie OC3, OC 12. One port protects the other. (Like 1:1 but optical)

1:N) 1 for N, 1 card protects N number of cards. In a 454 the protect card in slot 3 protect DS3 cards in slots 1,2,4 & 5.

Hope this helps,

Tim

[pvarney]

1+1 Optical signal transmitted along working and protect path at the same time. far end receiver determines which signal is the best and makes choice to switch without cordination with other end. Fastest switch time but you cannot run low priorty traffic over spare.

1:1 Optical Signal transmitted only on working path. Once LOS or other detected APS is intiated.

1:N If you have N channels (2,3, ...) they all share a common protection channel ... I think the cutoff is N=7 ... not sure ...

Hope this helps ....

[j.ketner]

While these are great protection types for cards, lets not forget that there are other protection types in the development of the ring. There is UPSR/BLSR, if we are looking at using the Ethernet Cards there are the APS/DPT protections. In order to clarify the protection scheme for you, it would be beneficial to know the type of protection that you are requiring.

With the card protections there are other aspects that you need to be aware of:

Such as

Y cables

Fiber Switched

All of this should be examined when looking at the design.