1/22/10

VoIP training

Good news!  A fabulous consulting company offered me a job on Wednesday.  Part of why it's so fabulous is because it embraces a variety of technologies.  One of which is Asterisk + Exchange installations.  This sounds very learn-able.  The concepts and keywords associated with telecommunications & VoIP are generally new to me...Teracom offers a full-sweep training package for $1,700.  It looks good.

I'm now getting up early in the morning for the first time in quit a while and feeling good for it.  As you may recall, I just purchased a big training package for MCITP / CCNA training.  My current thought is that I'm going to finish the MCITP training, then purchase the Teracom suite, then dive into VoIP.

1/20/10

Windows Mail: Outbox

If you're using Windows Mail and have a corrupt message stuck in the Outbox, try this hotfix from Microsoft.

1/12/10

DNS review

I'm sure you've noticed that some website URLs require the presence or absence of "www" in front of them in order to work. This is a DNS thing! If a site doesn't have a "www" DNS entry...then the URL won't work in your browser.

I remember the first time I ever saw a tech use NSLOOKUP - I asked him "How do you learn about tools like this?" One answer is to use a study package that teaches you through video and hands-on activities. :-)

Server 2008 introduces some new DNS features:
-> Background zone loading. I’ve never seen a heavily loaded DNS server, but presumably this helps a busy server start answering client requests right away, rather than waiting for the whole entire zone to be loaded first.
-> GlobalNames zone – this is cool, because you can now tell DNS about simple NetBIOS names (i.e. machines that are not in a domain), just like in WINS. Sweet!
-> Conditional forwarding can now be replicated in Active Directory (presumably in the past it was staying put on the individual DNS server).
-> Global Query Block List – this helps you keep hackers from registering an unwelcome computer name (e.g. a fake web proxy) on your DNS servers.
-> ...and RODC, LLMNR, DNSSEC, domain controller search, and IPv6/AAAA record support. I did not look into these.

1/7/10

VoIP Intro

I've been learning about VoIP lately. I'd like better sound quality for my calls than what my cell phone offers...however, that remains an elusive goal. I could try an IP Phone or a VoIP ATA (analog telephone adapter) for high audio quality.

Here's what I've learned so far:

You can test your Internet connection (or here) to see if you have enough bandwidth. Skype calls from my PC to their testing service sound great, but calls to my own voicemail or my parents' landline were terribly muffled. At first I thought this might be caused by my ISP maliciously tampering with VoIP packets, but poor audio quality remained even after signing up for and installing HotSpotVPN (an OpenVPN implementation). You do have to tell the VPN to use UDP instead of TCP.

I also tried VoxOx, but couldn't sign-in to my account with the program. Considered signing up with RingCentral.com, but $28/month would be overkill in this case. VirtualPBX.com looks very reputable, but is way too pricey for me at $50/month. Next, I looked at Google Talk, but for now it only does PC to PC calls (not landlines). Supposedly you can combine it with a free DID (Direct Inward Dial) number from GroovyTel to receiving incoming calls.

So, I signed up with IP Communications and purchased one SIP line (with one DID) for $10/month. This allowed me to receive calls on my new Bellevue, WA number, but not make outbound calls - for that, you have to sign in here and purchase a minimum of $10 credit. I think they debit your credit at the rate of 2 cents per minute or less. I'm using Counterpath's free X-Lite softphone. The audio quality isn't too bad, but isn't as good as I want it to be. I test it by calling my own voicemail.

IP Communications isn't the only SIP provider...VoicePulse.com and CallCentric.com both look interesting. VoicePulse may be less expensive than my current host.

This all-in-one $225 ooma Core VoIP Phone System (with no monthly fee) is big on Amazon.com - 717 reviews so far, with the vast majority being totally positive.

Reading up on "codecs" this evening...according to X-Lite's user manual, PC-only VoIP traffic can use "wideband" codecs that sample at 16 KHz, wheras calls into the PSTN require "narrowband" codecs (G711 only, in fact) that have a lower sampling rate. That explains why my test call into Skype sounded so much vastly better than to a landline. Maybe a Cisco IP phone would sound better...but that's a $100, so...not right now. :-)

1/6/10

Server 2008 Deployment

I've been learning about deploying Server 2008...editions, roles, features, etc.

::> The roles are: AD, DNS, DHCP, File (big upgrade from 2K3), Print, WSS (SharePoint), NAP (Network Access Protection), TS, IIS, and WDS (Deployment).
::> "Server Manager" in 2K8 replaces "Computer Management" in 2K3.
::> Editions: Web, Standard, Enterprise, Datacenter.
:: ::> The Web edition is identical to Standard except it only runs IIS. Standard doesn't offer ADFS (a type of single-sign-on), nor does it have as many features for handling certificates (such as an online responder or network device enrollment (for hardware which (naturally) doesn't have a domain account)). I'm not clear on what the "online responder" is all about. Standard is also "limited" to 32GB of RAM and 4 CPUs in a 64-bit configuration (4GB in 32-bit mode).
:: ::> Enterprise is the sweet-spot with up to 32GB/2TB of RAM (depending on 32/64-bit mode) and up to 8 CPUs. Enterprise also seems to allow you to legally run up to 4 additional installations in a virtual Hyper-V environment!
:: ::> The Datacenter edition can be scaled up to more CPUs - 32/64 for 32/64-bit respectively (you pay per CPU and user) and lets you legally run as many virtual installations of Windows Server as you dare!
:: ::> Pricing at the moment (from CDW.com) is $400 for Web, $740 for Standard (with 5 CALs), $2,900 for Enterprise (with 25 CALs), and $8,200 for Datacenter (4 CPUs). Info on licensing.

Server Core:
Let's say you have a limited-purpose perimeter server with some Internet exposure. You can reduce its attack surface by installing just "Server Core" which is the same as what you'd have normally, except all administration is done via Shell rather than GUI. It also doesn't support managed code in the form of .Net or ASP.net. Core also doesn't support ADFS, failover clustering, WDS, and probably other stuff too. It doesn't have an explorer.exe process. It's especially recommended as a foundation for Hyper-V guests (maximum performance).

About Windows PE and the Windows AIK..."PE" stands for Pre-execution Environment.

For upgrading from Server 2003, you have to boot into Windows and then insert your DVD - booting off the DVD only permits a clean install. AIK answer files for 2K8 are in XML (vs *.inf text files in the past)

Regarding WDS (Windows Deployment Services) and its images (*.wim file - "windows image"). WDS is a role. You can configure it to communicate with all PCs, no PCs, or only PCs in Active Directory. Well, you may ask, what if you want to use it with a brand-new PC? You "pre-stage" that PC by adding its MAC or GUID to a new "managed" computer account in AD.

Quite interestingly, you can use WDS to "capture" an existing server/PC image and save it for future reference. If you plan to roll that image out to additional boxes, be sure to use sysprep first. ImageX can be used to apply updates to an image.

NovaBackup

I suddenly remembered why my former employer originially standardized on "NovaBackup" for tape backup/restore. It's because (at least, at the time) it was the only program that would directly read the contents of a backup tape. Other programs demanded that you put in a specific tape to accomplish a restore...NovaBackup was willing to work with whatever you had available.