A reader writes "MPLS, or Multi-protocol Label Switching, seems to be a popular choice for router vendors nowadays until two AT&T researchers argue it differently. They "say MPLS create serious network management challenges for Internet backbone providers." "Even more dire are their warnings about potential security and privacy problems for companies that deploy MPLS-based VPNs." This issue will be discussed on an IETF meeting held this week in London. More details here ." Related to the IETF [?] , this submission came in: The Internet Engineering Task Force (IETF) is now meeting in London for IETF-51. You can watch multicast sessions. "