Job Description
Overview
Calix is a cloud and appliance-based platform and managed services company. Broadband service providers leverage the Calix broadband platform, cloud, and managed services to simplify operations, engagement, and service, innovate for their consumer, business. and municipal subscribers and grow their business and the communities they serve.
In 2010, Calix China Development Center, "凯易讯," was established in Nanjing Software Valley, located on Software Avenue, with convenient transportation. We are a team of nearly 300 professionals specializing in software and hardware development, testing, supply chain management, and project management, etc. Our team members come from other renowned companies in the IT and Internet industries. We collaborate with multinational teams from the United States, India, and other countries to develop core products.
As a member of the global software development team, you will participate in the design and development of Software in embedded systems.
After interning with this team for more over six months, you will:
Accumulate experience in the entire design, development, testing, and operation of enterprise-level software
Gain programming experience primarily in C, Python, Shell, etc.
Deepen your understanding of the development environment and ecosystem
Improve your problem-solving and analytical skills
Enhance your experience working in an all-English environment and collaborating with international teams
Internship Duration
The internship can start immediately upon successful interview
Work 3-5 days per week
The internship period is 6 months or longer
Responsibilities
Assist in the design, implementation, and testing of L2 protocols (e.g., Ethernet, VLAN, DHCP, IGMP, RSTP, Dot1.X, MPLS).
Collaborate with senior engineers to develop and optimize protocol algorithms.
Participate in code reviews and contribute to maintaining high code quality.
Conduct performance analysis and troubleshooting of L2 network issues.
Document development processes, test plans, and results.
Stay updated with the latest industry trends and technologies related to networking protocols.
Basic Qualification
Pursuing a bachelor’s or master’s degree, graduating in 2026 or 2027
Available for an internship lasting 6 months or longer
Major in Computer Science, Software Engineering, or a related field
Hands-on programming experience with C/C++
Experience with Linux software development
Able to work collaboratively in a team environment
Strong verbal and written communication skills
Preferred Qualification
knowledge of Linux user space and kernel space interaction, including:
Understanding of system calls, ioctl, and other kernel-user communication mechanisms
Familiarity with kernel-user data exchange and synchronization methods
Knowledge of network packet processing in the Linux kernel, including:
Understanding of packet reception, transmission, and forwarding in the kernel
Understanding of the kernel's network stack, including socket, TCP/IP, and Ethernet layers
Knowledge of packet forwarding and routing mechanisms in the kernel
Knowledge of Layer 2 protocols, including:
ARP (Address Resolution Protocol): understanding of ARP request and response, ARP cache, and proxy ARP
STP (Spanning Tree Protocol): understanding of STP topology, BPDU, and port states
DHCP (Dynamic Host Configuration Protocol): understanding of DHCP client and server, DHCP lease, and IP address allocation
IGMP (Internet Group Management Protocol): understanding of IGMP snooping, IGMP queries, and multicast group management
Allowance
200-280 RMB per day, adjusted based on the internship stage and performance.
Benefits
Outstanding interns will be added to the Calix talent pool and considered for full-time positions
Work in a global team with a multinational environment
Open and transparent culture with friendly and equal mentors and colleagues
Flexible working hours, no need to clock in
Flexible work location, with the option for remote work when needed
Adjustable desks and chairs for standing work
Free drinks, fruits, and afternoon tea
Free gym with shower facilities