How to Secure Hybrid Voice + Data Networks: From SIP to Teams Calling

Unified communications (UC) have emerged as a crucial component of firm management within a diverse work environment. Increasingly, voices of modern kinds, such as Microsoft Teams, are getting augmented by archaic modes of voice communication—say SIP trunking—so as to stay linked with the workforce as well as with partners and customers. Speech and data merge into a real-time event when used in hybrid networks, which, to give a few examples, include on-premise infrastructure, cloud environments, and remote endpoints—to produce strong cohesive ecosystems.

But it also enlarges the attack surface because, previously, voice data could only move between isolated legacy systems. Now, it traverses IP-based networks and cloud services, rendering it as vulnerable as all other digital assets. Attackers may now have access to attack points from remote connections, integrated collaborative tools, and cloud calling endpoints. They are no longer bound to internal systems.

This level of security was insufficient to ensure adequate protection in hybrid UC environments. A tiered, deliberate approach is necessary to keep such an environment secure. Strong security investments need to be applied to both the network edge and application levels to ensure safety for all voice and data connections from new threats.

Establishing Foundational Security for the Hybrid Network Core is essential.

Segmenting Voice and Data Traffic

One of the greatest best practices to follow is logically separating voice traffic from data traffic. VLANs (Virtual Local Area Networks) or distinct subnets would help prevent the compromise from one segment, such as ordinary data, to another segment, such as voice communications. Some of the benefits of segmentation are:

• Quality of Service (QoS): Prioritise real-time voice packets so that calls do not get dropped or distorted.
• Easier Monitoring: It allows for the identification of noticeable trends, such as a rapid rise in voice packet traffic that might indicate an assault.
• Limiting Lateral Movement: Access controls between segments also make things more difficult for an attacker who has access to one segment before gaining sensitive voice systems.

Network segmentation is undoubtedly the most crucial element in any hybrid network security plan. This really complicates the attack vector, making it much easier for the defences to monitor.

Robust Firewalls and Intrusion Prevention Systems (IPS)

Next-generation firewalls and intrusion prevention systems will be the core gears of defence against immoral acts. Deep packet inspection, threat intelligence, and the like can detect and block aberrant behaviours based on incoming and outgoing data networks. When firewalls are installed at the edge or inside segmentation points, even if attackers penetrate the outer shield, their movement within the network is greatly hampered by such measures. For well-managed signalling protocols and to prevent issues with SIP trunking and Teams Calling, different firewall rules are necessary.

Securing Voice Communication Channels: From SIP to Teams Calling

Encrypting voice traffic using SRTP/TLS and securing SIP trunks are essential components of protecting voice communication.

Voice communication contains highly private and confidential information, including contracts, agreements, intellectual property, personal identifiers, and health records, all of which require the same level of security provisioning as data flow. The text does not suggest that the security of conversations can be optional; it is mandatory.

Secure Real-Time Transport Protocol (SRTP) protects the voice data by simply encrypting the actual media stream against snooping and modification. TLS, also known as Transport Layer Security, integrates all SIP signals to maintain call setup, management, and termination. This feature prevents termination, spoofing, and replay attacks. If none of these cryptographic mechanisms exist, any hacker can take over the phone and listen to conversations or even cut communications.

Organisations that routinely use SIP trunking must ensure that the provider meets SRTP and TLS, which should be well established in their hosting/data centre partners' session border controllers (SBCs). SBCs are also quite important for securing a voice infrastructure, as they manage SIP traffic, and they impose rules like:

• Authentication of devices and control of access
• Rate restriction and traffic shaping to stop DoS or toll fraud attacks
• The system provides real-time monitoring and alerts for unusual behaviour or failed login attempts.

Hybrid voice systems are still open to a wide range of threats without these extra layers of protection, which puts both operational integrity and sensitive conversations at risk.

Protecting Microsoft Teams Calling Endpoints and Infrastructure

Large organisations use Microsoft Teams as their primary communication tool, yet its security is only as robust as its weakest point. To ensure the safety of Teams Calling, several preliminary settings are required. First, multi-factor authentication should be used to verify users' identities. Further, all devices must be stored and secured by all forms of advanced antivirus, EDR, and MDM solutions, laptops, mobile devices, or tablets; attacks may then show up there. Currently, maximising Microsoft's security stack by activating Defender for Office 365 and Compliance Manager would cover all aspects of identity and data protection. Administrators should also impose conditional access restrictions to determine where someone's location is, whether a device is compliant or not, or how risky the individual is when considering access authorisation.

Best Practices for Hybrid Network Security Management

Centralised Identity and Access Management (IAM)

Centralised IAM solutions, such as Azure Active Directory, provide hybrid network security. Organisations gain visibility and control over who accesses what, when, and where by integrating identity management across apps, including voice (like Teams and SIP endpoints) and data (like SharePoint and OneDrive). Role-based access control (RBAC), single sign-on (SSO), and just-in-time (JIT) access strategies help curb unnecessary access by users and reduce the risk of privilege escalation attacks.

Regular Auditing, Patching, and Security Awareness Training

Security is a continuous process that requires constant attention. It's done all the time. Companies should plan for regular security audits. Penetration tests and vulnerability scans may uncover holes that attackers have not yet discovered. This involves keeping SBCs, routers, Teams apps, and operating systems updated with the latest patches to protect against attacks that hackers can easily execute using well-known exploits. Human awareness is just as important. Employees are typically the first line of defence or the first thing that goes wrong. Ongoing security training enables employees to recognise phishing attacks, make secure communications, and adhere to the security rules of the organisation.

Hybrid telecom and data networks guarantee unparalleled freedom and efficiency but demand a considered and proactive approach to security. The organisation employs network segmentation, robust firewalls, strong encryption, centralised IAM, and continuous monitoring to safeguard unified communications and sensitive business information against current threats.

Test your defence before a breach occurs, so step in. Check your current security posture, implement the layered controls identified above, and ensure your team has the tools to detect and respond to issues before they escalate.

Engage the Anticlockwise Team to design and set up secure and reliable hybrid voice and data networks for your firm. Your reputation and communication are based on it.

Securing Voice Communication Channels: From SIP to Teams Calling

Encrypting voice traffic using SRTP/TLS and securing SIP trunks are essential components of protecting voice communication.

Voice communication contains highly private and confidential information, including contracts, agreements, intellectual property, personal identifiers, and health records, all of which require the same level of security provisioning as data flow. The text does not suggest that the security of conversations can be optional; it is mandatory.

Secure Real-Time Transport Protocol (SRTP) protects the voice data by simply encrypting the actual media stream against snooping and modification. TLS, also known as Transport Layer Security, integrates all SIP signals to maintain call setup, management, and termination. This feature prevents termination, spoofing, and replay attacks. If none of these cryptographic mechanisms exist, any hacker can take over the phone and listen to conversations or even cut communications.

Organisations that routinely use SIP trunking must ensure that the provider meets SRTP and TLS, which should be well established in their hosting/data centre partners' session border controllers (SBCs). SBCs are also quite important for securing a voice infrastructure, as they manage SIP traffic, and they impose rules like:

• Authentication of devices and control of access
• Rate restriction and traffic shaping to stop DoS or toll fraud attacks
• The system provides real-time monitoring and alerts for unusual behaviour or failed login attempts.

Hybrid voice systems are still open to a wide range of threats without these extra layers of protection, which puts both operational integrity and sensitive conversations at risk.

Protecting Microsoft Teams Calling Endpoints and Infrastructure

Large organisations use Microsoft Teams as their primary communication tool, yet its security is only as robust as its weakest point. To ensure the safety of Teams Calling, several preliminary settings are required. First, multi-factor authentication should be used to verify users' identities. Further, all devices must be stored and secured by all forms of advanced antivirus, EDR, and MDM solutions, laptops, mobile devices, or tablets; attacks may then show up there. Currently, maximising Microsoft's security stack by activating Defender for Office 365 and Compliance Manager would cover all aspects of identity and data protection. Administrators should also impose conditional access restrictions to determine where someone's location is, whether a device is compliant or not, or how risky the individual is when considering access authorisation.

Best Practices for Hybrid Network Security Management

Centralised Identity and Access Management (IAM)

Centralised IAM solutions, such as Azure Active Directory, provide hybrid network security. Organisations gain visibility and control over who accesses what, when, and where by integrating identity management across apps, including voice (like Teams and SIP endpoints) and data (like SharePoint and OneDrive). Role-based access control (RBAC), single sign-on (SSO), and just-in-time (JIT) access strategies help curb unnecessary access by users and reduce the risk of privilege escalation attacks.

Regular Auditing, Patching, and Security Awareness Training

Security is a continuous process that requires constant attention. It's done all the time. Companies should plan for regular security audits. Penetration tests and vulnerability scans may uncover holes that attackers have not yet discovered. This involves keeping SBCs, routers, Teams apps, and operating systems updated with the latest patches to protect against attacks that hackers can easily execute using well-known exploits. Human awareness is just as important. Employees are typically the first line of defence or the first thing that goes wrong. Ongoing security training enables employees to recognise phishing attacks, make secure communications, and adhere to the security rules of the organisation.

Hybrid telecom and data networks guarantee unparalleled freedom and efficiency but demand a considered and proactive approach to security. The organisation employs network segmentation, robust firewalls, strong encryption, centralised IAM, and continuous monitoring to safeguard unified communications and sensitive business information against current threats.

Test your defence before a breach occurs, so step in. Check your current security posture, implement the layered controls identified above, and ensure your team has the tools to detect and respond to issues before they escalate.

Engage the Anticlockwise Team to design and set up secure and reliable hybrid voice and data networks for your firm. Your reputation and communication are based on it.