Voice Systems

The mission of the Network Division's Voice Systems Unit is to provide superior voice telecommunications service. The unit manages seven (7) statewide voice contracts, assists agencies with project management and technical expertise, and reviews vendor-generated invoices. The Voice Systems Unit also manages nineteen (19) PBXs that are located within Multi-Service Centers (MSCs). Additionally, the unit manages both the Baltimore State Office Complex and the Annapolis Complex PBXs. The Baltimore and Annapolis complex PBXs provide telecommunications services for more than 16,000 users.

A major goal of the Voice Systems Unit is to connect most of the 350+ statewide PBXs by using networkMaryland(TM) as a voice transport infrastructure. This strategy will reduce long distance, local call and circuit costs for State agencies. This will begin a phased approach for the deployment of VoIP.​

Voice Systems SIP Trunks​




VoIP Carrier Connections via SIP trunking concurrent call paths (CCP).​

Features and Benefits

Next generation carrier connection through Session Initiated Protocol (SIP) trunks to a customer owned VoIP communication systems.

  • Unlimited Local and Domestic Long Distance Calls Included

  • Initial SIP Firewall (SBC) setup included

  • Supports for faxing over IP (FoIP)

  • Redundancy with multiple service providers and links

  • Ability to easily add or remove SIP trunks

Dept. Owner:

Voice Systems

Service Owner:

Alan J. Sabol
Alan J. Sabol

Support Contact:

Alan J. Sabol
Alan J. Sabol

Status: Currently offered


Eligible Customers

Enterprise Agencies Yes
Individual State Agencies Yes​
Counties No
Local Municipalities No
Public No

The service is available to any agency connected to the ESSB network.


Service Prerequisites


Before service can be offered the client must meet the following requirements:

DoIT Provided Services:
  • Connection to networkMaryland
  • Must have a connection to the Voice VPRN
  • Clients are responsible for ensuring their data network can support VoIP
  • Have programming information required to complete the installation

Notes: N/A


Scope of Service


This section outlines the area of responsibility between the provider (DoIT) and the customer.

In Scope:

  • Configuration of SIP trunks to route to the customer’s network

  • Modification of the DoIT managed SBC

Out of Scope:

  • Programming of customer owned VoIP communication system and voice mail systems

  • Installation of premise wiring

  • Modification of any equipment that is directly connected to the Customer’s network

Customer Responsibilities:

  • Validating all provided network information is correct

  • Customer is responsible for securing their own network

  • Ensuring all network settings are properly configured to pass voice traffic

  • Arranging meetings with third-party vendors when required

  • Supporting their data network and troubleshooting VoIP issues to the network demarcation (DMARC)

Service Level Agreements

Category Enterprise Customer Standalone (Non-Enterprise) Customer
Availability: 99.9% Uptime 99.9% Uptime
Capacity: Varies by location and equipment Varies by location and equipment
Service Hours: 7 x 24 7 x 24
Maintenance Schedules:
  • As required – with minimum of 48 hours notice.
  • As required – with minimum of 48 hours notice.
Upgrades and Refreshes:
  • As required – with minimum of 48 hours notice.
  • As required – with minimum of 48 hours notice.