• Is Managed Services the IP Telephony of 2010?
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SIP (Session Initiation Protocol)

SIP is by far the most popular protocol used in VoIP communication today. SIP was designed as a signaling protocol in charge of setting up and tearing down sessions between two or more devices. Additionally, SIP can be used to modify existing sessions. The protocol was designed to be independent of transport protocols. Thus, SIP can be used over both TCP and UDP. As of this writing, popular open source PBX Asterisk only supports SIP over UDP.

H.323

H.323 isn’t a single protocol as much a system of protocols. It is an ITU recommendation focused on providing multimedia communication in IP networks. On of its strengths over purely audio-based protocols is the ability to provide video conferencing. Other protocols often used in conjunction with H.323 include H.225 for call signaling, H.245 for call control, and Real-time Transport Protocol (RTP) for multimedia communication.

MGCP (Media Gateway Control Protocol)

Like SIP, MGCP is a signaling protocol. Unlike SIP, MGCP relies on another protocol, Session Description Protocol (SDP), to handle session creation and termination. MGCP was originally designed to handle scaling issues experienced by large service providers. The original purpose of the protocol was to handle communication between call routing devices and media conversion gateways. For example, MGCP might be used between an Asterisk server and a Cisco AS5350 Universal Access Server connected to the PSTN.

SCCP (Skinny Client Control Protocol)

Skinny is a proprietary protocol originally developed by Selsius Systems and now owned and maintained by Cisco Systems. Although proprietary, open source versions of the protocol have been implemented. Although Cisco 7900 series phones use Skinny to communicate with Cisco CallManager, the SMB-targeted Linksys IP phones use SIP.

Inter-Asterisk Exchange (IAX / IAX2)

IAX was designed to provide call control functionality between Asterisk PBXs. One of the benefits of IAX is that both control and data traffic are included in the same stream. Therefore, if a connection can be established, audio will pass successfully. This is not true of signaling protocols that rely on other protocols to provide audio traffic. This makes IAX particularly useful in firewalled / NATed environments. Mark Spencer detailed the benefits of IAX versus SIP.

If you have other vendors you would like to see on this list, send me a message. I’ll keep updating the list until we have everything we need.

Apple Inc.

• Apple security updates
• Apple security-announce mailing list

Cisco Systems Inc.

• Cisco Security Advisories and Notices
• Cisco Notification Service
• Cisco Security Advisories RSS feed

The FreeBSD Project

• FreeBSD Security Information
• freebsd-security-notifications mailing list
• Send email to freebsd-security-notifications@freebsd.org with the word ‘help’ in the subject or body.
• FreeBSD Security Advisories RSS feed

Google, Inc.

• Google Online Security Blog

Microsoft Corporation

• Microsoft Security Newsletter
• Featured Security and Privacy Content RSS feed
• Microsoft Technical Security Notifications mailing list

Red Hat, Inc.

• Security announcements for Red Hat Enterprise products
• Security announcements for all Red Hat products and services
• Red Hat Errata RSS feed

Sun Microsystems, Inc.

• Sun Security Blog
• Sun Security Blog RSS feed

The key to limiting the choices to staff members only is the limit_choices_to argument to the model ForeignKey field. For example:

class Computer(models.Model):
  admin = models.ForeignKey(User, limit_choices_to={'is_staff': True})

In the above example, objects in our Computer class have an administrator that must be a staff user. This separates them from other users in the company that may not be staff members.

• How P2 Changed Automattic — Matt Mullenweg
• Close .tpl access with .htaccess
  You can do this in your Apache configuration file, too.
• Cisco confirms exit from WiMAX RAN market – Rethink Wireless
• The Right Way to Add Custom List Markers to Unordered Lists | Impressive Webs Toronto

I use labels extensively, and about 100 of these messages are labeled as either “security” or “cisco.” The emails in these labels need to be reviewed closely, so I’m going to go ahead and exclude them from this search. Therefore, the search below will find all unread messages in my inbox, unless they are labeled as “security” or “cisco.”

is:unread in:inbox -{label:security label:cisco}

This should be entered in the Gmail search box. The only really tricky things here are the curly braces ({}) and minus sign (-). The curly braces treat everything inside as if it was separated by a logical OR. In this case, it matches any message that is labeled “security” or “cisco.” WIthout the curly braces, a message would have to be in both labels to match. The minus sign lets Gmail know that I don’t want to see the results of that match in the final search results.

• Xensource updates apt repository missing GPG key | Steve Glendinning
• Cisco exiting WiMAX market
• An analysis on the DNSKEY query storm problem | Internet Systems Consortium

• Gartner EXP Worldwide Survey of Nearly 1,600 CIOs Shows IT Budgets in 2010 to be at 2005 Levels
  Virtualization tops the technology priorities.
• Cisco Offers Three-Year, Zero-Percent Financing to U.S. Small and Medium-Sized Businesses -> Cisco News
• Marc Alff's blog: Performance schema overview
  Really interesting stuff for MySQL developers.
• Locating and managing the IS security function

If you have an interest in information security from both a technical and managerial level, check out Principles of Information Security. It does an excellent job of presenting material for both audiences.

Cisco Systems Inc.

• Multiple Vulnerabilities in Cisco Security Agent
• Multiple Vulnerabilities in Cisco ASA 5500 Series Adaptive Security Appliances
• Cisco Firewall Services Module Skinny Client Control Protocol Inspection Denial of Service Vulnerability

Red Hat, Inc.

• RHSA-2010:0095 Important: rhev-hypervisor security and bug fix update
• RHSA-2010:0112 Critical: firefox security update
• RHSA-2010:0113 Critical: seamonkey security update
• RHSA-2010:0114 Critical: acroread security and bug fix update
• RHSA-2010:0115 Moderate: pidgin security update
• RHSA-2010:0119 Low: JBoss Enterprise Web Server 1.0.1 update

Sun Microsystems, Inc.

• A Security Vulnerability in Solaris Pidgin (see pidgin(1)) May Allow Remote Unprivileged Users to Access Arbitrary Files

• Coding Horror: The Great Newline Schism
• Use Tab-completion for SSH 'host' aliases
• Geek Run – Affordable Xen VPS and cPanel shared hosting
  Inexpensive virtual private servers based in LA.
• Setting up a web service with Django and SOAP
  If you need to create a SOAP-based web service for your Django app, Ray's tutorial is a really nice introduction to using soaplib.