Several remote sales employees, who have come into the office this week, report that they are unable to get on the Internet, but no other users have reported similar issues. The helpdesk has escalated

IP addresses beginning with 169.254.x.x are APIPA addresses, which are self-assigned by a client when it cannot obtain an IP address from a DHCP server. This strongly suggests that the DHCP server is either down, misconfigured, or unreachable from the client's network segment, preventing the clients from receiving valid network configurations.

While network switches could be involved if there's a connectivity issue preventing DHCP requests, the specific APIPA address points more directly to the DHCP service itself rather than general network connectivity.

A DNS server issue would prevent name resolution but would not cause clients to obtain 169.254.x.x IP addresses; they would still get an IP from DHCP.

The core router handles routing between networks but is not directly responsible for assigning IP addresses to end clients within a local subnet via DHCP, although it might be the gateway.