Joel Cunningham Email & Phone Number

Responsible for design and architecture of DPU packet processing data plane software for virtualization of multi-tenant networking (VCN) for compute workloads within OCI.Operational leader and responsibilities for hyper-scale fleet of DPUs within OCI.Work with business stakeholders to design, scope, and plan business-unlocking DPU network virtualization features.

Software Development Engineer on the Virtual Cloud Network Data Plane team at Oracle Cloud Infrastructure.Responsible for high performance C based packet processing data plane that translates between virtual cloud networks and the underlying physical network.Designed and lead high risk (potential SEV1 blast radius) project to switch all internet bound traffic in OCI to a new packet encapsulation format. Designed control plane signaling mechanism to ensure multiple distributed packet processing fleets could switch over with no customer outage.Experience working with bind9 providing virtual cloud DNS service. Helped identify and root cause a CVE crash in bind9 when receiving truncated TSIG responses.Implementation and testing of data plane features to support Layer-2 network virtualization, specifically enforcement of network security groups for L2 VNICs, communication between L3 subnets and L2 VLANs, and aggregate throttling for broadcast traffic.

Remote work arrangement as an embedded software engineer on the WiFi technologies team. Responsible for wireless technologies in embedded Linux and RTOS based products.Experience and familiarity with using Open Embedded and Yocto for building embedded Linux consumer electronics.Ported MediaTek's MT6630 Linux driver from kernel 3.10 to 4.9, integrating with ~30 API breaks in the cfg80211 and netdev subsystems. Wrote a Yocto recipe to deploy configs, firmware, and user space programs for the MT6630.Develops and maintains the Lightweight IP (LwIP) TCP/IP stack, which provides network communications (with WiFi/PPP link layers) for devices running an in-house RTOS. Active developer on the LwIP project and have contributed a number of feature improvements:1) Vectored I/O: Implemented sendmsg for sockets API and vectorized the TCP output infrastructure2) Implemented TCP Appropriate Byte Counting (RFC 3465) to improve transmit performance3) Re-worked the TCP persist timer to ensure TCP receive window is fully closed and zero window probing times out the connection4) Implemented parts of 'Advanced Sockets API for IPv6 (RFC 3542)': CMSG, ifnamextoindex, IP_PKTINFO, etc.5) Contributed a number of socket and TCP unit tests. Ported unit test framework to build on MacOS with Clang

Remote work arrangement as an embedded software engineer on the WiFi technologies team.Experience studying and understanding the Linux kernel networking and wireless subsystems (cfg80211/nl80211, netlink, and netdev). Implemented equivalent subsystem layers for porting Linux wireless drivers to an embedded RTOS.Optimized FFmpeg HTTP seeking for video playback by allowing short seeks within the TCP window to continue reusing the same connection rather than abort the connection and open a new one for each seek. In our target use case, this optimization significantly reduced the number of connections used (from ~180 to ~5) and reduced the data sent by the server.Developed and maintained ports of the following open source projects for wireless devices running an embedded RTOS:1) NGINX web server. Devices utilize NGINX for serving content (static and dynamic) to mobile applications connected to a local wireless network. Designed and implemented custom NGINX module to generate dynamic content by executing in-memory generators. This avoids using an additional upstream HTTP server/FastCGI daemon for dynamic content. Familiarity with NGINX architecture and internals.2) Lightweight IP (LwIP) TCP/IP stack. Devices utilize LwIP to provide applications with a Berkeley sockets interface and TCP/IP communications. LwIP integrates on top of a custom wireless link-layer. Active contributor to the LwIP project.4) WPA supplicant. Devices utilize WPA supplicant as part of the wireless subsystem to provide WPA/WPA2 authentication.3) jrptlib. Garmin Virb action cameras utilize jrptlib for RTP and RTCP communication. jrtplib is controlled through an in-house RTSP server. Experience working with h.264 and AAC transport over RTP.4) mDNSResponder. Devices use mDNSResponder to provide applications with a DNS-SD API and mDNS capabilities (query, browse, and advertise support).

Olathe, Kansas

Senior Software Engineer responsible for product and technology development of embedded Marine electronics.Developed and maintained embedded C TCP/IP stack for networked Marine electronics. Studied internet RFCs and TCP/IP stacks (Linux, BSD, and lwIP) implementations.Ported Apple's open source mDNSResponder to embedded RTOS in order to facilitate use of Multicast DNS for Marine electronics.Developed DHCP server with distributed lease database and migration features. Lease database replicates across network hosts through consensus synchronization framework. DHCP server migrates to new host during failover and can renew existing leases.Functioned as Network Owner for connectivity products in the Marine system. Responsible for networking roadmap, designing, implementing, and reviewing network solutions.

Olathe, Ks

Embedded C software engineer responsible for product and technology development of Marine electronics.Developed TCP/IP networking expertise by implementing embedded TCP/IP stack for ARM products. Designed and implemented network application protocols for networked sensors.Extensive experience debugging network stacks, file systems, embedded operating systems, and network applications.Designed and implemented hierarchical database for storage of string key, value pairs. Implemented a Radrix Trie backend to optimize lookups/insert/deletes and reduce required memory.Responsible for map database development, performance improvements, and maintenance. Designed and implemented map database digest file format feature. Digest file improved map scanning performance by an order of magnitude and was critical to the product shipping.Played critical role in developing network technologies for blackbox sonar project. Worked with Lead Software Engineer to deliver product within deadline given numerous unknowns.

Manhattan, Ks

Responsible for administering Gentoo Linux servers for the K-State Computing and Information Sciences department.Administered Apache, DNS, DHCP, NFS, Samba, and SSH servers. Utilized cfengine for managing configuration of servers. Employed Nagios for performance monitoring. Wrote custom python and bash scripts for batch processing needs.Maintained custom Gentoo Linux computer labs images via local Gentoo binary package repositories.

Olathe, Kansas

Worked on one of the Marine software teams to added NMEA2000 communication support to an in-house RTOS Linux boat simulator. Worked with another simulator that provides a first person experience of driving a boat. Improved performance and fixed bugs.

Kansas City, Missouri Area

Engineered and implemented features in front end applications and middleware scripts to query person records from a person database.Responsible for applying, analyzing, and testing waiting time calculation changes in middleware scripts, for universal health care solutions in the United Kingdom.

Pittsburg, Ks

Responsible for installation, configuration, and maintenance of workstations and servers running Debian Linux.Installed, configured, and managed an OpenBSD router, firewall,and network address translation (NAT) machine.Configured and managed various network services including Apache, DHCP (ISC), DNS (BIND), Network File System (NFS), Packet Filter (PF), proxies (Squid and Privoxy), and secure shell (SSH).