Blog Articles
ExpiredDrayTek continuously strive to launch new innovative products and champion business continuity solutions. This blog page will provide in-depth background knowledge on key technologies driving modern computing networks
What is Carrier Grade NAT (CGNAT) ?
Michael SpalterFebruary 2022
The entire IPv4 address space of the Internet provides approximately 4 billions unique IP addresses. That was more than anyone ever conceived would be needed when the Internet started. Every device on the early Internet had its own unique public IP address.
What is SD-WAN?
Michael SpalterFebruary 2022
If you're an IT professional, working in or with SMEs, you've probably seen the terms Software Defined Networking (SDN) and Software Defined WAN (SD-WAN) being used and often touted as "the next big things".
The right technology for your home or shed office
Melanie CharlesNovember 2021
More of us are working from home than ever. Earlier this year, the UK’s Office for National Statistics (ONS) found that 25.9% of the working population, or 8.4 million people, had worked from home for at least part of their week in 2020, up from 12.4% in 2019.
A brief history of Wi-Fi (802.11a to 802.11ax)
Michael SpalterSeptember 2021
With the new 802.11ax wireless standard becoming mainstream, today I am looking back at the evolution of wireless LAN which is now 20 years old.
How does a DSL line work?
Michael SpalterSeptember 2021
In this article, we go a lot deeper technically and examine how a DSL line actually works. How does your data get turned into a signal that can travel down a regular wire phone line?
G.Fast, Supervectoring & VDSL2
Michael SpalterSeptember 2021
VDSL (Very High Speed DSL) covers several technologies all using FTTC (Fibre To The street Cabinet. The street cabinet has a fibre optic feed back to the BT (or other) network and then uses a regular line - copper wire - to the customer premises.
Wi-Fi Brute Force Attacks
Michael SpalterJune 2021
If a hacker wants to access your network wirelessly, he/she will need its password. They might just be able to get it by seeing it written on a whiteboard, post-it note or by using another social engineering method. If they can't get the Wi-Fi password, just as if a burglar doesn't have a key to your apartment, he/she has to use brute force to get in.
Forward Error Correction
Michael SpalterJune 2021
There are many systems and protocols under the Internet bonnet (hood) that we users can just take for granted. That our data arrives with us perfectly is just one of those luxuries and it's down to error correction systems - magical automatic systems that we didn't always have. In this article I'll explain how data integrity is preserved on the Internet, and also most other modern digital storage and communication systems.
DOCSIS (Cable Internet) - What is it and how does it work?
Michael SpalterJune 2021
DOCSIS is the modern standard used for 'cable modem' Internet (and triple-play) service in the UK and in most other countries. Compared to DSL (carried on twisted copper pair phone lines) and fibre (using light over glass-fibre cables), DOCSIS uses coaxial cables ("coax") to carry RF (radio frequency) signals to each home or office. Coax uses a single central conducting wire and an outer shield to prevent the signal from leaking along the path as shown in the picture at the top of this page.
Cable Modem Troubleshooting & Disconnection Problems
Michael SpalterMay 2021
"Cable Modem" or just "Cable" service is generally used to describe Internet or TV/Phone service provided over coaxial cable using DOCSIS technology. This is provided mostly by Virgin Media (Liberty Global) in the UK and all carriers in North America. Most cable companies do also provide DSL and pure fibre ('FTTP') service so always be sure about exactly what type of service you have.
What is QAM and how does it work?
Michael SpalterMay 2021
In my recent article on Wi-Fi 6, I explained that a coding method called QAM was at its heart. QAM is also used in cable modems (DOCSIS), which I'm covering in another article soon. Explaining QAM is unnecessarily complex to have included in the original Wi-Fi 6 article, but I promised to explain it later and, being such a brilliant and elegant method, it's worth understanding
GPON Fibre - ONU (Subscriber 'Modem') Activation
Michael SpalterApril 2021
In a previous article on GPON fibre, I focussed on the hardware components which make up a GPON installation: The OLT (active box at the end of the street), the passive splitters (along the street), the ONU - the box in your home or office that terminates the fibre and converts to Ethernet or Wi-Fi and the various cables, plugs and sockets.
GPON - What is it and how does it work?
Michael SpalterApril 2021
With Openreach's ambition to have an all fibre network, end to end to every home and office within the next 15 years, fibre is one of the technologies that we'll all need to be familiar with, just as we learnt about analogue modems, ISDN, ADSL, VDSL and cable modems in previous times.
MIMO & Beamforming
Michael SpalterApril 2021
When I was writing my recent article about how 802.11ax (WiFi 6) works, I mentioned MIMO and beamforming, I recalled all of the times I'd had questions about these, the confusion between them and a misunderstanding about what they actually do.
Ofcom Relax the Rules on the 5Ghz Band
Michael SpalterMarch 2021
After campaigning by vendors and users, Ofcom announced two important decisions in July 2020 relating to the 5Ghz band; that was quite timely as vendors prepare to introduce more 802.11ax devices in that band and usage will therefore increase.
WPA3 - What is it, and what's new?
Michael SpalterMarch 2021
An open wireless network - one without any authentication or encryption allows anyone within range to intercept and view any other user's sent or received data. Today, it's likely that much of that data itself is encrypted as we secure TLS-secured web sites (HTTPS), use VPNs or other secure protocols and for that reason, using such services in a public or shared Wi-Fi facility is still acceptable.
How does 802.11ax (Wi-Fi 6) work?
Michael SpalterMarch 2021
Existing wireless LAN (Wi-Fi) standards, from 802.11b through to 802.11ac are to be joined by the latest standard, 802.11ax. In order to make these standards easier to recognise in marketing and use, new friendlier names have been adopted. 802.11ax is known as "Wi-Fi 6" and we'll use that term in this article.
The End of Analogue Phone Lines (Part 2)
Michael SpalterFebruary 2021
In Part 1 of this article, we covered the 2025 switch of analogue phone lines/service in the UK. In this, part 2, we are going to look at some of the practical implications that will affect users who still want phone service and how they will migrate to replacement services
The End of Analogue Phone Lines (Part 1)
Michael SpalterNovember 2020
In 2025, Openreach will be switching off their analogue phone service ("POTS"). If you still have an analogue phone plugged into a regular 'BT' socket on the wall, it will no longer work By June 2021 Openreach will already no longer install or accept new analogue line orders for lines at 120 exchanges around the UK, with that number increasing over time.
2.4Ghz vs. 5Ghz Wi-Fi - Which is better?
Michael SpalterAugust 2020
Usage of the 5Ghz Wi-Fi band is increasing. The 5Ghz band was used for 802.11a, introduced in 1999 but 802.11a wasn't widely adopted - later systems such as 802.11b through to 802.11n used the 2.4Ghz band. More recently, the 5Ghz band has been used for 802.11ac and again now for the latest 802.11ax standard. In this article, I'll explain the benefits and downsides of the 5Ghz band compared to the more commonly used 2.4Ghz band.
Firefox and DoH - What you need to understand
Michael SpalterAugust 2020
If you're an IT technician, a SysAdmin or generally interested in such things, you may already know about DoH, but for everyone else - regular users of the Internet, with some browsers in some regions - they've just had a fundamental part of their web's inner working changed. They won't notice, but the change is fundamental and has impact beyond the claimed benefits that those responsible are making.
VPN Service Providers - Are they overpromising?
Michael SpalterAugust 2020
This blog article is brought to you by...actually, just us but if you watch online vloggers or any volume of online content, you're likely to have seen adverts for "VPN Services". They might be static or video adverts or, increasingly, content sponsorships where the presenter will interrupt his or her main content to read a script explaining why you should use a VPN service.
Antenna Theory, Gain & Bands
Michael SpalterJune 2020
Many users of Wireless LAN (WiFi) equipment will have heard the word 'gain' in relation to the aerials (antennae) on your wireless router or access point. It is generally assumed that the more 'gain' an aerial provides, the stronger your signal will be and thus your coverage range will increase. Therefore you might assume that for maximum range, you should use the highest gain aerial you can find.
What is Two Factor Authentication (2FA)?
Michael SpalterJune 2020
When you log onto a web site, server or service, you'll commonly use a username and a password. The username may be your email address or otherwise easy to guess and is not 'secret' but the password should be complex and not possible to guess - the password is your secret factor.
What is 'Pen Testing' and do I need it?
Michael SpalterJune 2020
According to reports, "the proportion of attacks targeting home workers increased from 12% of malicious email traffic before the UK's lockdown began in March [2020] to more than 60% six weeks later." With increased teleworking, it becomes harder to maintain a uniform and properly enforce security policy.
The new EU eCall system for cars
Michael SpalterJanuary 2016
Last year I wrote an article on the DrayTek blog discussing the privacy risks of letting official (government) apps live on your smart phone, about how they might taddle on you any time you're up to no good.
It may be game over for privacy-lovers though. Forget your cellphone - your new car already has the tracking built-in.
Do you really want your driving licence on your phone?
Michael SpalterMarch 2015
The US state of Iowa is the latest to introduce electronic (app-based) driving licences (or 'drivers licenses'). In the USA, drivers are required to always carry their licence and insurance and provide it to a police officer who may stop them.