John C. Lin

Bell Laboratories
Networking Software Research Department

791 Holmdel-Keyport Road
Room M-230G
Holmdel, NJ 07733, USA
1-732-888-7162
johnlin@bell-labs.com

Projects:

• Low Latency Layer-3 Handoff Protocol for 802.11 WLANs: We designed and implemented a scheme to support low-latency layer-3 handoff for 802.11 wireless mobiles roaming between Access Points (APs) that are connected to different IP subnets. The scheme uses link-level frames (e.g., ARP and 802.11 management frames) to send route updates to the mobiles and to an Access Router (AR), which serves as the gateway to the Internet. This approach allows for IP packet routing to and from a mobile to begin immediately after the mobile establishes a link-level association with a new AP. The design does not require modifications to the mobiles. Each mobile maintains a fixed IP address and a fixed default router address as it moves from one AP to another. The APs and the AR cooperate to track each mobile and forward packets using IP tunneling. Experimental results from our implementation show that the scheme can achieve handoff latency on the order of a few milliseconds.
  
  
• AP-PCF: AP-PCF is a Wi-Fi (802.11) Access Point that allows Wi-Fi clients to access CDMA2000 networks through a single account, without requiring the AP-PCF to have access to user account information. It extends CDMA2000 packet data services to Wi-Fi users. By deploying it, CDMA2000 network service providers can offer packet data services to their subscribers not only via a CDMA2000 device but also a Wi-Fi mobile device. The same account authentication and billing procedures are used for both types of access. In short, AP-PCF simplifies user account management for the service providers and expands the CDMA2000 service areas to include Wi-Fi hot-spots.
  
  
• Lucent WebCache:  This project focuses on the design and implementation of a high-performance HTTP proxy cache for Lucent as a product in the content distribution domain. The cache code achieved 983 PolyMix3 requests per second using 5 10K RPM 18G SCSI-2 disks and a single 100 Mb/s fast Ethernet interface in the third Cache Bake-off (the latest PolyMix3 performance results are available here). Currently, the cache code is being used to handle all the HTTP traffic originated from the Bell Labs research networks in New Jersey.
  
  
• Reliable Multicast: This is a joined work with Sanjoy Paul and Krishan K. Sabnani.We designed and implemented a reliable multicast transport protocol called RMTP. RMTP uses intermediate receivers (called Designated Receivers) to store received packets and provide data retransmission for receivers downstream. The scheme avoids the ACK implosion problem at the sender, reduces retransmission latency, and saves network bandwidth. (paper)
  
  
• Crosspoint: This is my PhD thesis project (a joined work with my advisor Doug Comer and Vince Russo at Purdue). We designed and implemented a wireless, mobile internet using 3 PCs running Xinu OS as WaveLAN base stations. An ATM switch interconnects all the base stations and a router. To provide wireless coverage for the CS building, each base station is placed on each floor of the building. Students using a laptop PC with a WaveLAN card can roam in the building and maintain their TCP connections to the Internet. There is no need to install additional software on the laptop PCs to access the Crosspoint network. Base stations communicate with each other using ATM PVCs, emulating a single wireless, mobile network that covers the entire CS building. (paper)

Research Interests

• TCP/IP internetworking: reliable multicast, mobile computing, wireless networking.
• Client-server applications: web caching, high performance server design and implementation.
• Network securities: network intrusion detection.

Publications

• Probing TCP Implementations
  Proceedings of 1994 Summer USENIX, pp. 245-255, June 1994.

• TCP Buffering And Performance Over An ATM Network
  Journal of Internetworking: Research and Experience, Vol. 6(1), pp. 1-13, March 1995.

• RMTP: A Reliable Multicast Transport Protocol
  Proceedings of 1996 IEEE INFOCOMM, pp. 1414-1424, March 1996.

• Reliable Multicast Transport Protocol (RMTP)
  IEEE Journal on Selected Areas in Communications, Vol. 5, No. 3, pp. 407-421, April 1997.

• An Architecture For A Campus-Scale Wireless Mobile Internet
  Purdue CS Technical Report CSD-TR 95-058, Sept. 1995.

• A Laboratory Environment For Experimenting With Xinu
  Purdue CS Technical Report CSD-TR 96-047, Jan. 1996.

Education

• B.S.: National Taiwan University
• M.S.: Georgia Institute of Technology
• PhD.: Purdue University
  (Dissertation: An Architecture For a Campus-Sized Wireless Mobile Network)