Doctoral Thesis: Enabling Configurable, Extensible, and Modular Network Stacks

Wednesday, April 13
11:30 am - 1:00 pm

32-G449 (Kiva)

Akshay Narayan


While applications’ traditional networking stack has remained stable for three decades, a recent trend toward more in-network services and a supporting set of new network hardware has transformed networking stacks. These network services provide a rich set of features, such as load balancers to support scalability or hardware acceleration of encryption.
Unfortunately, in this new landscape individual libraries are tied to specific environments (such as a specific cloud provider’s network) and datapaths (DPDK, RDMA, etc). As a result, changing runtime environments or the implementation of a particular feature can involve reimplementing large parts of an application’s code. Especially today, with applications relying on third-party libraries and network features, changing an application’s extended network stack–-including not only the operating system’s traditional packet transport functionality but also modern libraries which facilitate the use of network services and hardware–-is considered daunting enough to cause “lock-in” to cloud networks and libraries. I will thus discuss Bertha and CCP, two systems that improve this new landscape. Bertha, a new extensible and runtime re-configurable network stack which extends flexibility and layering to applications’ use of network features, addresses the difficulty of writing modern applications. CCP is a proposed restructuring of datapaths’ congestion control functionality designed to support congestion control algorithms across multiple datapaths, and for new datapaths to support many congestion control algorithms with one-time effort.


  • Date: Wednesday, April 13
  • Time: 11:30 am - 1:00 pm
  • Location: 32-G449 (Kiva)
Additional Location Details:

Thesis Supervisors:  Professors Hari Balakrishnan and Mohammad Alizadeh