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359

As you can see from the output, you aren’t actually pinging some server in Arizona or even the United States. Apparently, they decided to protect their website with Cloudflare, which employs a content distribution network to even the load. A CDN works with many nodes, each servicing a (geographic) region. That means the node you’re pinging is very close to ...


179

The short answer is: some sort of interrupt system. Essentially, they use blocking I/O, meaning they sleep (block) while waiting for new data. The server creates a listening socket and then blocks while waiting for new connections. During this time, the kernel puts the process into an interruptible sleep state and runs other processes. This is an important ...


87

It depends on the tool. For most purposes the two will be the same, but not always. For example, if you use a 3-digit number starting with a zero (or a two-digit one starting with zero, thanks @Dietrich-Epp), then ping will assume the numbers are octal. Microsoft Windows [Version 6.3.9600] (c) 2013 Microsoft Corporation. All rights reserved. ...


75

Yes there is. Any electronics device will have capacitors that will store energy even after you unplug it. You may have noticed when you unplug, say a monitor or TV, the little diode will take another second or two to discharge remaining energy from the capacitors in form of electricity and stop glowing. This residue energy may not allow memory chips to ...


71

This serverfault answer has good guidance on what to do, but since you (I mean, me) asked for tools and measurement.. Below are some good tools, first for understanding connectivity health within the local wifi network, and then to an internet endpoint. Wifi Tools NetSpot (for mac) It tracks the local WiFI APs and provides basic data like SNR, Channel, ...


58

Assuming all software you are using is using dot-decimal and subnetting correctly, yes they are the same. 192.168.0.1 for example is only the friendly dot-decimal notation of the dot-binary value 11000000.10101000.00000000.00000001. Whether you type it as 192.168.0.1 or 192.168.000.001 they are both equal to 11000000.10101000.00000000.00000001


54

"explain to my home broadband supplier that I want a dedicated IP address coming to my house so that people can ping a teapot" just not reference the teapot... they could think you're crazy! By the way: just tell them you want a static ip address. Please Note that in many countries, many ISP don't sell static IPs to consumer-class customers (but asking ...


53

Web server doesn't send "entire website", but documents that browsers request. For example when you access https://www.google.com/ the browser queries server for the document https://www.google.com/. The server processess the request and sends back some HTML code. Then the browser checks what the server has sent. In this case it's HTML webpage, so it ...


53

Please be aware that a system can handle more than 65536 concurrent connections, because they do not necessarily each use a separate port. A TCP connection or UDP flow is defined by the 4-tuple: (source IP address, source port, destination IP address, destination port) So even if you have a web server machine with just a single IP address, and a single ...


44

On Windows CMD if you put leading zeros on the IP address means octal. It is interpreting 016 as 16 octal and converts it to 14 decimal. You can use octal, decimal or hexadecimal notation as in the following example: 22.101.31.153 (decimal) 026.0145.037.0231 (octal) 0x16.0x65.0xF1.0x99 (hexadecimal)


42

HTTP does not care about—and is independent of—any of the lower-level protocols used to transport itself, even though it is itself stateless. The transport technology can be TCP, or Novell’s old SPX, or SCTP, or whatever else you can dream up, and HTTP will still work the same. HTTP does require a streaming or connection-oriented protocol—and depends on ...


39

By definition on a layered model as OSI or TCP/IP each layer works independent and not-aware of the lower layers. When you remove the cable, it's a physical disruption (layer 1), so almost inmediately ethernet (layer 2) detects a loss of signal (if you're on Windows you will see the very dreaded pop-up informing network disconnected) IP (layer 3) and TCP ...


33

Latency is generally independent of bandwidth. Latency, as commonly measured by ping times, is an indication of how long it takes for your system to send data to another computer and to receive its response. Latency is influenced primarily by how far the data must travel—it takes much longer to access a webpage on a server that is halfway around the world ...


33

No. You need to configure so the routers have different IPs. Preferable, you assign 192.168.0.1 to the Virgin router, and 192.168.0.2 to the Sky router. This you do with the Sky router disconnected from the Virgin router, via a wireless client. Also, you need to turn off the DHCP server on the Sky router. Then connect the Sky router from LAN port to LAN port ...


32

No, your router should block incoming access to your LAN just like it would if it was connected directly to the Internet. He may be able to sniff your Internet traffic though (since he's between you and the Internet). Perhaps check out these other SU questions: How much information can my ISP see? What information can my ISP see from my router?


29

This is what dig any ejn.nu returns: ejn.nu. 60 IN SOA ejn.nu. root.ejn.nu. 18 604800 86400 2419200 604800 ejn.nu. 60 IN A 217.211.179.99 ejn.nu. 60 IN NS ns2.sudonet.net.ejn.nu. ejn.nu. 60 IN NS ns1.sudonet.net.ejn.nu. ejn.nu. ...


27

The different networking layers are there to allow them to be swapped for different technologies. The two layers you are talking about here are layers 2 and 3. Layer 2 in this scenario is Ethernet - from which MAC addresses arise, and Layer 3 is IP. Ethernet only works at the local level, between network devices connected to a broadcast network ...


25

The word might just be "IPv6". It's entirely reasonable for a teapot to have an IPv6 address. The design of IPv6 allows you to have a whole subnet of IPv6 addresses for all devices in your home.


24

I would suspect that they do. I don't believe that text-based browsers will (by default) even download resources such as images or external entities, such as fonts (if needed), scripts, etc. I did some basic testing with tcpdump trying to get this IANA page (http://www.iana.org/domains/reserved) with both lynx and then wget, and here were my results (HTTP ...


24

"What kind of IP address is this? (WIN-F9PTTKUMI2U:29901)" WIN-F9PTTKUMI2U:29901 is not an IP address. It identifies a socket connection of a particular μTorrent peer and has the format hostname:port. WIN-F9PTTKUMI2U is the hostname. 29901 is the port number. Source Peers: The Peers tab is where you'll find information about all the peers you ...


24

The other answers are basically correct, but I thought I'd expand on the topic. Hopefully this information will be useful. As long as you have your router in a standard configuration, it should block unsolicited incoming network connection attempts, essentially acting as a blunt firewall. Port Forwarding Settings which increase your exposure surface would ...


23

It depends on the tools or functions any given program uses to parse the address given. Both Microsoft and Linux as well as other OSes use a POSIX compatible inet_addr() routine for parsing addresses. Many TCP/IP programs such as Ping and FTP use the inet_addr() sockets function to translate IP address strings into 4-byte addresses. This function accepts ...


23

Q: How do they get that many publicly-routable IPs? Your school could possibly have a static IP address range assigned to them by their Internet Service Provider (ISP), by virtue of the fact that a school district is a fairly large customer (orders of magnitude larger in terms of money than a single family home, to be sure). Note that you can't simply ...


23

You can use freely any Private Network Address. http://en.wikipedia.org/wiki/Private_network RANGE 10.0.0.0 -- 10.255.255.255 172.16.0.0 -- 172.31.255.255 192.168.0.0 -- 192.168.255.255 Refer to RFC 1918 for background Keep in mind the Network address and Broadcast Network: Host Address Broadcast Address ...


21

Neither of you are wrong, you just asked Google a different question from your actual question. If you had explained to Google that you meant GiB and MiB, it would have given the answer you expected. Try this: 1000 GiB / 1 MiB


20

Does it have to be an IP address? The reason I ask is that it would be much easier (and cheaper) to use a domain to access it. Doing this, you could maintain the same internet connection you have now at home, and use a service like dyn.com or noip.com to keep your domain (htcpcp.com maybe?) pointing to your home internet's dynamic IP. That way, when your ...


20

There's nothing called "address of the local computer". IP addresses bind with network interfaces. If you have 5 LAN/Wifi cards (network adapters) in your computer then you can have 5 IPs for those interfaces. Here what you see is the adapter named "Local Area Connection" with IP address 192.168.1.36, while 127.0.0.1 is the address of the loopback adapter ...


20

Only some programs allow to split processes over the network (some 3D rendering programs, effectively sharing RAM) (See answer of Julian Knight) The problem with internet would be that's too slow (See answer of Spiff) I think the RAM of your desktop won't be hardware compatible, so just placing the RAM strips into your laptop won't work. What you can do: ...


18

The location of DNS servers is irrelevant to network speed. The DNS server informs your system about the IP address of the site you're looking for. After that the DNS is out of the way, the name - IP address correspondence is cached for a period of time and you are connected directly to the IP. If your ping is taking more than 200 ms, the problem lies ...


18

I’m wondering if the maximum speed of a network card would reduce the chances of a DDoS affecting a home-hosted website. Not really. Perhaps the network bandwidth could be saturated to the point of the network connection being unusable, but a faster network connection would not prevent that from happening. It would only delay the inevitable by ...



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