H. Balakrishnan, V. Padmanabhan, S. Seshan, R. H. Katz, "A Comparison of Mechanisms for Improving TCP Performance over Wireless Links," IEEE/ACM Transactions on Networking, (December 1997). [PDF]

Summary

Unlike wired networks, congestion is not the only source of packet loss in wireless networks. Networks with wireless and lossy links also suffer from significant losses due … Continue Reading ››

V. Bharghavan, A. Demers, S. Shenker, L. Zhang, "MACAW: A Media Access Protocol for Wireless LANs," ACM SIGCOMM Conference, (August 1994). [PDF]

Summary

The media in a wireless network is a shared and scarce resource; as a result, controlling access to this shared media to maximize performance is one of the key issues in wireless … Continue Reading ››

Y. Chen, R. Griffith, J. Liu, A. Joseph, R. H. Katz, "Understanding TCP Incast Throughput Collapse in Datacenter Networks," Workshop on Research in Enterprise Networks (WREN'09), (August 2009). [PDF]

Summary

This paper presents a diagnosis of the TCP incast collapse problem and proposes a framework for a solution that should be:

1. generalized: not limited to … Continue Reading ››

V. Vasudevan, A. Phanishayee, H. Shah, E. Krevat, D. G. Andersen, G. R. Ganger, G. A. Gibson, B. Mueller, "Safe and Effective Fine-grained TCP Retransmissions for Datacenter Communication," ACM SIGCOMM Conference, (August 2009). [PDF]

The TCP Incast Collapse Problem

In data centers with high-fan-in, high-bandwidth synchronized TCP workloads, receivers can experience a drastic … Continue Reading ››

A. Greenberg, J. R. Hamilton, N. Jain, S. Kandula, C. Kim, P. Lahiri, D. A. Maltz, P. Patel, S. Sengupta, "VL2: A Scalable and Flexible Data Center Network," ACM SIGCOMM, (August 2009). [PDF]

Summary

VL2 is a scalable data center architecture to provide uniform high capacity between servers, performance isolation between services, Ethernet layer … Continue Reading ››

R. N. Mysore, A. Pamboris, N. Farrington, N. Huang, P. Miri, S. Radhakrishnan, V. Subramanya, A. Vahdat, "PortLand: A Scalable Fault-Tolerant Layer 2 Data Center Network Fabric", ACM SIGCOMM, (August 2009). [PDF]

Summary

PortLand is a scalable, fault-tolerant, and easily manageable layer 2 routing and forwarding protocol for data center environments that exploits the knowledge … Continue Reading ››

C. Kim, M. Caesar, J. Rexford, "Floodless in SEATTLE: A Scalable Ethernet Architecture for Large Enterprises," ACM SIGCOMM Conference, (August 2008). [PDF]

Summary

SEATTLE is an enterprise network architecture that combines the scalability of IP networks with the simplicity of Ethernet without incurring respective drawbacks. It uses flat address space to provide plug-n-play functionality and … Continue Reading ››

S. Kandula, R. Mahajan, P. Verkaik, S. Agarwal, J. Padhye, P. Bahl, "Detailed Diagnosis in Enterprise Networks," ACM SIGCOMM Conference, (August 2009). [PDF]

Summary

Diagnosis of generic and application-specific faults in networked systems is known to be notoriously hard due to dynamic and complex interactions between components. This paper presents NetMedic, a system that enables … Continue Reading ››

D. Katabi, M. Handley, C. Rohrs, "Congestion Control for High Bandwidth-Delay Product Networks," ACM SIGCOMM Conference, (August 2002). [PDF]

Summary

Regardless of gateway queueing schemes, TCP becomes inefficient and suffers from instability as per-flow product of bandwidth and delay increases. The main reason is that the existing TCP queueing mechanisms are not fast enough to … Continue Reading ››

S. Floyd, V. Jacobson, "Random Early Detection Gateways for Congestion Avoidance," IEEE/ACM Transactions on Networking, (August 1993). [PDF]

Summary

Random Early Detection or RED detects impending congestion based on average queue size and notifies connections of congestion through binary feedback by dropping packets or by marking bits in headers. To this end, RED uses two … Continue Reading ››