If you have a dedicated/leased line, between two offices, can the information be intercepted or sniffed?
Yes, information can be intercepted or sniffed at either end or between your WAN links; the latter requires physical access to tap into your wire -- to protect against this, encrypt data between your sites. If your WAN routers use valid IP addresses, no access control list, and are not protected by a firewall, then these routers are exposed to external probes. Keep in mind, that if your routers are being monitored (pinged) by an outside company for high availability, ICMP should be restricted - both in your firewall and routers - to that company only.
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