SAN Protection

The ONS 15454 supports a variety of protection options when performing SAN extension. These protection options depend on which type of SAN extension card you use. Table 8-3 defines the path-protection options for the SAN extension cards that are available on the 15454 SONET platform and the 15454 DWDM platform.

Table 8-3. Path-Protection Options for ONS 15454 SAN Extension

SAN Extension Card	Path-Protection Options on ONS 15454 MSPP	Path-Protection Options on ONS 15454 DWDM
FC-MR-4 (4 ports)	Trunk protection: Unidirectional path-switched ring (UPSR), bidirectional line-switched ring (BLSR), Path Protected Mesh Networking (PPMN), protection channel access (PCA), unprotected
10G MR Transponder (1 port)		Client side: Y cable Trunk side: Unprotected (1-XFP client to one trunk interface)
2.5G MR Transponder (1 port) (2 card versions: unprotected and splitter protected)		Client side: Y cable for unprotected trunk option Trunk side: Splitter protection or unprotected (1-SFP client to one or two trunk interfaces)
2.5G Data Muxponder (8 ports) (2 card versions: unprotected and splitter protected)		Client Side: Y cable for unprotected trunk option Trunk side: Splitter protection or unprotected (8-SFP client to one or two trunk interfaces)
10G Data Muxponder (8 ports)		Client side: Y cable Trunk side: Unprotected (8-SFP clients to one trunk interface)

Protection for the transponder and muxponder cards includes client-side protection using Y cables and wavelength splitter protection. Automatic protection switching (APS) is supported when you select wavelength splitter protection on the 2.5G transponder and 2.5G muxponder cards. This enables you to protect the traffic on a DWDM ring because the transponder and muxponder card transmits the traffic from the storage device (such as MDS 9000) in both the east and west directions on the ring. Less than 50 ms switchover to the protect wavelength occurs when the working path fails or the performance degrades.

The 10G transponder and 10G muxponder do not support wavelength splitter protection. However, you can provide trunk-side protection by using two transponder cards or two muxponder cards. A Y-cable can be used to connect to a single trunk interface on the storage device. Keep in mind that this same configuration applies when using the unprotected card version of the 2.5G transponder and 2.5G muxponder.

Y-cable protection is supported on all the DWDM transponder and muxponder cards and is an optional feature. This means that there are two identical client-side cards in the ONS 15454. These two cards are configured as a protection group, which means that one card is designated as the working card and the other card is designated as the protecting card. Only one of the two client transmitters is on at any given time. If the working path fails, the transmitter on the protecting card is turned on, and the transmitter on the working card is turned off.