ISU is composed of four departments:

Network Operation Center (NOC)
The center hosts the hardware and software required for operating the  Internet in Saudi Arabia. The NOC main tasks are to route traffic in and out of the  country, block access to unsuitable material on the Internet, provide technical  support for ISPs and universities, and carry on other tasks needed for proper  operation and development of the center.
 

Saudi Network Information Center (SaudiNIC)
The center is responsible for domain name registration under the ".sa" hierarchy; The center also manages the IP address space for some organizations, and is in charge of providing Internet-related information to ISPs, universities, and subscribers through the ISU web site.
 

Network Security Center (NSC)
This center is in charge of all security aspects of Internet access, This includes blocking of unsuitable Internet material, safeguarding of internal network operations, providing protection against viruses and hacking attempts by providing technical information and advise, warning of any security problems detected in software and hardware it learns about whether internally or through outside parties,  in addition to any other security measures needed for maintaining a secure  Internet service in saudi Arabia.
 

ISP Relations Department (IRD)
This department is in charge of issues related to ISPs, such as the management of ISP accounts and the planning for ISP development and success. The department is in  charge of maintaining proper ISP accounts and making any adjustments to billing charges, as well as handling bandwidth upgrades and provisioning.

The National Root CA (National Root CA)
The main goal of the National Root Certification Authority (NRCA) is to oversee the development of the Public Key Infrastructure (PKI) in Saudi Arabia in coordination with other concerned agencies.
The main tasks are as follows :
- Qualification of agencies interested in obtaining a licence for becoming a Certification Authority.
- Issuance and revocation of CA certificates, and maintaing a Certification Revocation List (CRL).
- Operating and maintaining the National Root CA equipment and software.
- Preparing the policies, rules, and regulations that are needed for PKI.
- Working with CA’s and assisting in the Coordination among CA’s.
- Coordination programs for the development of NRCA Human Resources.
- Preparing periodic reports on NRCA’s Activities.
- Preparing NRCA’s annual budget.
- Other tasks as required.

Administrative and Financial Support
Department Objective:
- Carrying out all administrative and financial tasks which relate to the function of ISU in coordination with other concerned departments Functions.
- Carrying out all accounting tasks of the ISU.
- Follow-up of ISP accounts and governmental agencies which connect directly to ISU.
- Follow-up of ISP invoice collection tasks.
- Preparing the financial statements of the ISU.