Maybe a quick IP and DHCP primer is needed. I'll make it the simplified
version appropriate to most home networks.
Every device ("host" in traditional TCP/IP speak) on your network has a
unique 48 bit Media Access Control (MAC) address, usually described as
six groups of hexadecimal bytes, e.g. 00:11:22:33:44:55 with the first
part of the address representing the manufacturer of the device and the
latter part assigned to individual devices. MAC addresses do not provide
any information about what network segment a device is on. It's worth
noting that many (most?) devices allow their MAC address to be manually
configured, in effect appearing on the network as a different device
which can present some considerable security and management concerns.
An IP address (version 4, unicast, what you are likely still using) is a
32 bit number generally described as a dotted group of 4 octets, e.g.
192.168.1.1 which, in the context of a subnet mask, provides the
location of a device on a specific network segment. Most home networks
use a subnet mask of 255.255.255.0 which indicates that the first 3
octets identify the network segment and the last octet identifies
individual hosts on that segment (up to 254). Your home network is a
private network that uses IP numbering not routed on the public
Internet. Instead, your "router" performs a trick called Network Address
Translation (NAT) to manage communications between Internet hosts and
the devices on your network. How NAT works is not relevant to this
discussion but it turns out that very few home routers actually do any
routing as they only handle communications between a single internal,
private network segment and the Internet.
IP networking has to be configured properly for all hosts to communicate
with each other. By far the most important rule is each IP address is
uniquely assigned to one host. A host can have multiple IP addresses,
but no hosts can be assigned the same IP address (we aren't going to go
into the configuration of fault-tolerant clusters which share a virtual
IP address).
All hosts on the same network segment should have the same subnet mask,
gateway address (typically the router's internal IP address) and DNS
servers (typically those provided by your ISP and/or your router's
internal IP address). The gateway is the IP address of the device that
should receive data for hosts not on the local network segment, i.e.
anything that doesn't start with 192.168.1. Domain Name System (DNS)
servers are hosts which provide name resolution to allow us to use
human-friendly names for hosts instead of numbers. That's why you can
get here using forums.slimdevices.com instead of 107.21.6.57. Unless you
have a computer on your internal network running DNS, you will only use
it to resolve public Internet names.
As the network administrator, you are responsible for planning and
configuring your network. You will decide what network addressing to use
and will assign individual IP addresses to hosts with the appropriate
subnet mask, gateway and DNS entries. You have options as to how to
accomplish this.
You could assign manually IP addresses to all devices on your network
and maintain a list of them. These are static addresses and the
configuration for each is stored on the individual devices. New devices
have to be manually configured as needed. If you assign the same address
to more than one device they will not function properly. If you mistype
any of the configuration entries the device will not function properly.
For small networks that rarely change, assigning static IPs may be
tolerable but for most people it quickly becomes unmanageable.
So you can use a Dynamic Host Configuration Protocol (DHCP) server to
manage the configuration for you. In this scenario you still need to
have one static IP address (typically your router which is also the DHCP
server), and you configure DHCP to assign IP addresses to devices
configured to use DHCP. When those devices initialize their network
interface, they broadcast a DHCP request and negotiate an IP address
with the DHCP server that responds. The DHCP server provides the IP
address, subnet mask, gateway, DNS and a lease duration (and potentially
other configuration options not generally found on a home router).
Unfortunately, most of these items are not configurable on most home
routers (including yours). You will only be able to assign a range of IP
addresses to use (the scope). The other information is based on the
configuration of the router. Your router does not allow you to exclude
IP addresses from the scope, so make sure you do not use the whole range
(2 - 254) if you want to assign any other static IPs.
Of particular interest is the lease duration, an important DHCP feature
that is rarely addressed specifically by home routers. In the
negotiation between the DHCP server and the network device, the server
only provides an IP address that it considered available within its
scope; one that does not have a current lease, reservation or
exclusion). When it provides it do the network device it does so only
for a specific length of time which could be as little as minutes or
hours or as long as days. If the device does not renew its lease, the
DHCP server will make it available within the scope to assign to another
device. So it's important that the DHCP server and the devices that use
it are kept in sync. If the DHCP server is reset, it may consider all
addresses in the scope to be available which could lead to it handing
out leases for IP addresses already in use by devices on the network.
One way to mitigate DHCP issues is to assign a reservation for devices
which are typically on your network (your router has this feature). By
entering the MAC address of the device and assigning an IP address from
the DHCP server's scope, no other device will be assigned that IP
address and that device will always be assigned that IP address when it
makes a DHCP request. You can make reservations for wired and wireless
devices. The other IP addresses in the scope will be used for transient
devices, presumably your guests' laptops, cell phones, tablets, etc.
I hope this was helpful. It doesn't address wireless issues but we can
examine that later.
Win7Pro(x64)[3.3Ghz i5, 8GB RAM, 120GB SSD system, 15TB storage], LMS
7.7.3 -> Logitech Squeezebox Classic V.3 -> Cambridge Audio DacMagic ->
NAD C160 -> 2 x NAD C272 -> Quad 22L2
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