What does couchbase consider a WAN to be?

Hi,

We have an ACTIVE-ACTIVE dual-datacenter where we run web services from. The sites are less than 5km apart and we are already replicating SAN traffic in real time with low latency (ie gigabit fibre link). (i.e. DBs commit on remote write ack)

Some services are simple stateless farms that just serve up pages, others are stateful and form a cluster.

We are currently looking at how to replicate the data from side A to side B and vice versa. We have options of using a multicast node discovery method (messy and doesn't scale well), a stretched network using dark fibre between sites, or couchbase running over the normal network between sites

We want to replicate this statefull data to all nodes and one consideration was to use couchbase to store this replicate this data.

However, i see that Couchbase is not intended for the WAN . What does Couchbase consider a WAN to be in terms of link speed and latency. i.e. will our consideration of couchbase pass this first requirement?

Cheers,

KB.