>can I dedicate a separate link with 100M for replication only and how we can do it.
Replication happens between the ESX hosts on the protected site to the vSphere Replication appliance at recovery site.
Initial replication traffic happens through port 31031 and ongoing replication happens through 44046. I'm not a networking expert but if you can manage to route replication traffic(both initial sync and ongoing) from multiple ESX hosts (assuming you have multiple hosts 
)on the protected site to the 100mb link it should be possible. Source :- http://goo.gl/VTL8a
>second thing I am actually upgrading from SRM 4.1 to SRM 5.1 so the data is replicated by storage so can I use the data as seed copies to minimize >replication between main site and DR site, I need help on that urgently
If you can somhow manage to mount the (replicated by the array) Luns/VMFS volumes on the DR site, possibly by resignaturing the lun/vmfs volume, you get the option to browse and select the vmdk disk on the recovery site when enabling replication for a VM. The advantage of this is, you will not be using bandwidth for the initial sync but for delta changes only.
Hope that answers your query.
Regards,
K1@ud
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