Latest Articles

Cisco Meeting Server Load Balancing with Call Bridge Groups


Sunday, June 24, 2018

In a previous article here, I discussed Cisco Meeting Server Load Balancing with a focus on the Cisco Unified Communications Manager configuration and load balancing from its perspective. This article expands that discussion with the Call Bridge Group feature added in CMS version 2.1. Note this article does not cover all the requirements of implementation, please refer to the official Cisco documentation that I have referenced below. Also, note that Load Balancing Calls Across Cisco Meeting Servers omits configuration required to make the solution work.


Cisco Meeting Server Graphical Space Extractor


Tuesday, April 24, 2018

The Graphical Space Extrator is a small utility for connecting to a Cisco Meeting Server via API and extracting the configured CoSpace’s and there associated AccessMethods into a CSV file for review. Requirements The following is required in order for the utility to work: Microsoft .Net Framework 4.6.1 or higher The Cisco Meeting Server webadmin must be configured with a valid certificate The Windows computer where the utility is run must trust the certificate Install The Graphical Space Extractor can be installed from here.


Skype for Business Meeting Invitation Customisation


Tuesday, February 20, 2018

In a video conferencing deployment more often then not integration with Microsoft Skype for Business is a key component. To maintain a simple and familiar booking process for users the Skype Meeting invitation is modified to provide guidance on how to participate in meetings from video conferenicng devices. As shown below. Configure Skype Meeting Footer Text This below steps assume a vanilla Skype for Business build, adjust them as required to suit your environment:


CMS Wildcard Certificate With Skype for Business


Thursday, February 1, 2018

When testing Cisco Meeting Server (CMS) in a lab environment utilising a wildcard certificate (CN:*.sfblab.assured.io) for the callbridge I discovered that Skype for Business (SfB) would not accept inbound calls, however, SfB clients could make outbound calls to the CMS successfully. Subsequent research revealed that there is a known problem noted in the Acano FAQs here: Calls to Lync fail to connect and the error shown in Lync logs show “The peer is using a wildcard certificate but did not identify itself with a NEGOTIATE request”.


Cisco Spark SSO With Azure Active Directory


Friday, December 15, 2017

Integrating Cisco Spark with your Microsoft Azure Active Directory for Single Sign-On (SSO) enables users to enjoy the benefit of authenticating with Spark using their Active Directory credentials, and bypassing the password login altogether if they are already authenticated in the browser to the Office 365 cloud. In this article, I describe the process of configuring Cisco Spark with the Microsoft Azure AD for SSO with screenshots for context throughout. I’ve assumed you have an existing Cisco Spark and Microsoft Azure AD available and the required permissions to follow the steps that follow.


CMS as a CUCM Conference Bridge


Wednesday, November 15, 2017

A brief article detailing how to configure the Cisco Meeting Server (CMS) as a conference bridge resource in Cisco Unified Communications Manager (CUCM) for ad-hoc call escalation. OpenSSL is used only for example purposes, in production, a more appropriate certificate authority should be used for signing certificates in your production environments. Create a Root CA using OpenSSL Generate a key and the certificate to use for signing CSR requests as a root certificate authority.


SipOps SIP Testing Tool


Tuesday, November 7, 2017

SipOps and PySipOps are an extension of some work posted in a previous article SIP OPTIONS with Scapy. PySipOps is a basic version of SipOps written as a simple example. SipOps is written in Java and supports sending the following SIP messages SIP Early Offer Invite (& SIP ACK) SIP Delayed Offer Invite SIP Options It is a simple piece of code and not meant to be a commercial SIP testing tool replacement by any means, nor is it designed to be a fully fledged SIP UA.


SIP OPTIONS with Scapy


Friday, October 20, 2017

“Scapy is a powerful Python-based interactive packet manipulation program and library.” which I recently used to identify an issue with some incoming SIP OPTIONS pings to a Cisco Expressway. This article, as an output of working through the issue, provides the python script to perform (a) a TCP handshake, and (b) craft a SIP OPTIONS message and send it towards a device, which in this case is a Cisco Expressway. An in-depth overview of TCP or general packet manipulation is not discussed, however, as an aside, I’ve found that some of the existing Scapy TCP three-way handshake code used an incorrect TCP SYN number on the subsequent TCP PUSH/ACK packet following the handshake which is accounted for in the code below.


Cisco Meeting Server - Load Balancing


Thursday, August 31, 2017

The Cisco Meeting Server load balancing document referenced can be found here. The section titled Example 3: Deployment without a SME to route calls, describes the configuration required to route calls to a dispersed set of CMS’s trunked locally to their respective CUCM clusters. Through the use of Route Groups, Route Lists, Route Patterns, and Transformations, the CMS deployment can be made more resilient, allowing calls to flow to alternate CMS servers in the cluster through a remote CUCM cluster with local CMS resources when the local CMS is unavailable or busy.


Cisco Expressway SfB Federated Call Problems


Wednesday, July 19, 2017

This article will cover various issues found pertaining to federated calls between Microsoft Skype for Business (SfB) and Cisco’s collaboration platform via the Expressway appliances. SfB Client Reports “We couldn’t reach xxxxx@ciscoenv.domain.com” This issue was encountered when trying to call from an Office 365 SfB client into a Cisco CMS space via Expressways. Initial investigation showed that the Expressway-E’s received no inbound communication from the Office 365 cloud when the SfB client tried to initiate the call.