A Virtual Private Cloud (VPC) that enables both RDMA and TCP provides advantages for both tenants and cloud providers. It serves the flexible demands of RDMA and TCP of tenant applications while delivering a cost-effective solution compared to the construction of two distinct overlay networks. In this study, we introduce Jakiro, an innovative framework of vNIC design that supports both RDMA and TCP within ByteDance Cloud. Jakiro holds the capability to support fundamental VPC features such as QoS, security groups, etc., for both RDMA and TCP streams while maintaining compatibility with applications and intra-host RDMA optimization techniques. We benchmark Jakiro's performance using basic test cases and real-world high-performance computing applications and distributed machine learning training. The results indicate that the RDMA performance of Jakiro is close to that of the physical RDMA. Concurrently, Jakiro guarantees a weighted fair QoS between RDMA and TCP. Jakiro has been deployed in ByteDance Cloud for one year, we share our critical design and deployment decisions, as well as experiences and lessons from production.

Cloud providers, such as AWS and Azure, have started providing 5G services on their cloud infrastructure. In this paper, we present the design and implementation of X-Plane, a system that uses commercial programmable ASICs and DRAM servers on today's cloud infrastructure to implement high-performance 5G User Plane Function (UPF). Building X-Plane is hard because we need to address the following challenges: consistency issues when concurrently accessing UPF state data, slow UE table lookup due to repetitive and numerous Packet Detection Rule (PDR) matching, and the need to handle out-of-order packets from disconnected UEs. X-Plane addresses these challenges by designing three novel technologies: concurrent state data access protocol, fast flow table and paging buffer for handling out-of-order packets. We demonstrate its feasibility and practicality with our implementation on a Tofino-based programmable ASIC. Our evaluation shows that X-Plane can support over ~490Gbps throughput per ASIC pipeline, over 10 million UEs, and finish packet processing within predictable ~4 us on average.

This paper presents CellFusion, a system designed for high-quality, real-time video streaming from vehicles to the cloud. It leverages an innovative blend of multipath QUIC transport and network coding. Surpassing the limitations of individual cellular carriers, CellFusion uses a unique last-mile overlay that integrates multiple cellular networks into a single, unified cloud connection. This integration is made possible through the use of in-vehicle Customer Premises Equipment (CPEs) and edge-cloud proxy servers.

A great many problems in network information theory, both fundamental and applied, involve determining a minimal set of inequalities linking the Shannon entropies of a certain collection of subsets of random variables. In principle this minimal set of inequalities could be determined from the entropy region, whose dimensions are all the subsets of random variables, by projecting out dimensions corresponding to the irrelevant subsets. As a general solution technique, however, this method is plagued both by the incompletely known nature of the entropy region as well as the exponential complexity of its bounds. Even worse, for four or more random variables, it is known that the set of linear information inequalities necessary to completely describe the entropy region must be uncountably infinite. A natural question arises then, if there are certain nontrivial collections of subsets where the inequalities linking only these subsets is both completely known, and have inequality descriptions that are linear in the number of random variables. This paper answers this question in the affirmative. A decomposition expressing the collection of inequalities linking a larger collection of subsets from that of smaller collections of subsets is first proven. This decomposition is then used to provide systems of subsets for which it both exhaustively determines the complete list of inequalities, which is linear in the number of variables.

Determining the rate region of a network is of great importance in the research area of network coding. Lots of attempts have been made and significant progress has been achieved over the last decade on this topic. Although these researches provide us with multiple ways of calculating the outer or inner bounds of rate region, the sheer complexity of the problem, which involves expressing and projecting a very high dimensional polyhedra, makes it computationally infeasible beyond networks with 10s of edges. Aimed at reducing the complexity of the rate region calculation, in this paper a new theorem that implicitly determines the rate region of a network is proved and a corresponding systematic way of applying the theorem to calculate explicitly the outer bounds to a rate region is proposed. Compared with the traditional method, the proposed method has the potential to calculate the true rate region via the projection of simpler polyhedra that has exponentially less dimensions and is characterized by exponentially less facets.

A new method is presented, consisting of exclusively simple linear algebra computations, for computing the linear programming Shannon outer bound to the network coding capacity region of a directed hypergraph network. This linear algebraic formulation enables a new upper bound on the worst case complexity of computing the Shannon outer bound to a network coding capacity region to be determined.