You probably heard about switches for LAN but not a lot of people heard about KVM switches. So what exactly is KVM switch?

If we look at the name, it is a shortcut for Keyboard, Video & Mouse and the original idea was to have multiple computers but one keyboard, mouse, and monitor. These peripherals would be connected to the KVM switch and other computers could all use one set of these on the fly when needed.
The technology behind the switch is a little interesting since it will actively fake signals to other computers that are not using peripherals. Once they are switched to them the transition is smooth and not noticeable. In old days these switches were more important than today since on every mouse or keyboard disconnection you had to reboot the computer, and although today that is not the case CPU will still detect disconnection and on the next connection it will run through the ID of the device and try to use the existing driver and if peripheral was connected in other USB port, it will install the same driver but connect it to the new USB port.
This type of reconnection can slow down work and place unnecessary load on the CPU so that is why KVM will fake connection in order to make switching externals on the computer smooth and in nick of a time.
Modern KVM switch
These days modern KVM switches will offer you more options than just being able to switch between keyboard, mouse, and monitor. Modern switches now offer Lan, audio, and many more various options.
There are also different kinds of switches offering you only one option, like for example just a Video switch that will let you use one monitor on three computers and many more other specialized options.
Software switches
So far we talked about Hardware switches, a real device being able to take peripherals into it and switch computers on the fly. On the other line, we have software switch solutions that will have specific software installed on all computers and have it run at all times, and switching between them will be through specific software.
There are two very good and main advantages of using software solutions instead of a hardware one. First, of course, is the price, since the most popular Synergy is an open-source solution, completely free of charge. The second big advantage is that software switch is not limited to how many computers can you use. Hardware switches tend to go to a large number like 16 but if you have a large cluster of computers over a LAN, let's say 30 then the box solution might be difficult.
On the other hand software solution will switch only keyboard and mouse since each other computer will have to have some screen on it in order to work. Both solutions have their strong advantages and disadvantages and it is up to you to choose one that best suits you.
Conclusion
If you are multitasking with a lot of computers or just need your peripherals from time to time to connect to another machine then the KVM switch is something that you might find the use of. Just be aware that if you go for some cheap switch you might experience some lag on your peripherals, but if that is not a concern you can get hardware one for as low as $50 USD.


The true cause is that there is no working Border Gateway Protocol (BGP) routes into Facebook's sites. BGP is the standardized exterior gateway protocol used to exchange routing and reachability information between the internet top-level autonomous systems (AS). Most people, indeed most network administrators, never need to deal with BGP.
Cloudflare VP Dane Knecht was the first to report the underlying BGP problem. This meant, as Kevin Beaumont, former Microsoft's Head of Security Operations Centre, tweeted,
"By not having BGP announcements for your DNS name servers, DNS falls apart = nobody can find you on the internet. Same with WhatsApp btw. Facebook has basically de-platformed themselves from their own platform."
Many people are very annoyed by this and with the fact that they cannot use their social media platforms but it seems that Facebook employees are in even bigger annoyance as it was reported that Facebook employees can't enter their buildings because their "smart" badges and doors were also disabled by this network failure. If true, Facebook's people literally can't enter the building to fix things.
Reddit user u/ramenporn, who claimed to be a Facebook employee working on bringing the social network back from the dead, reported, before he deleted his account and his messages:
"DNS for FB services has been affected and this is likely a symptom of the actual issue, and that's that BGP peering with Facebook peering routers has gone down, very likely due to a configuration change that went into effect shortly before the outages happened (started roughly 1540 UTC). There are people now trying to gain access to the peering routers to implement fixes, but the people with physical access is separate from the people with knowledge of how to actually authenticate to the systems and people who know what to actually do, so there is now a logistical challenge with getting all that knowledge unified. Part of this is also due to lower staffing in data centers due to pandemic measures."
Ramenporn also stated that it wasn't an attack, but a mistaken configuration change made via a web interface.
Both BGP and DNS are down, the "connection to the outside world is down, remote access to those tools don't exist anymore, so the emergency procedure is to gain physical access to the peering routers and do all the configuration locally."
Technicians on site don't know how to do that and senior network administrators aren't on site.
It seems that it will all be down for a couple of more hours before the issue is resolved. 