Transcript Implementation of VoIP at Broadway Suites

Implementation of VoIP at
Broadway Suites
2/9/2005
Broadway Suites
• Service Provider for downtown
Boulder office buildings, including
Executive Suites
– Multiple, diverse businesses in one
space
– Fortune 500 services on a small company
budget
Broadway Suites
Broadway Suites VoIP
• Broadway Suites was the first
Avaya VoIP implementation
in Colorado.
• Network Assessments didn’t
exist! We ‘learned by doing’
• As my spell checker
says, it was VoID!
VoIP Bedrock
– IP Numbers are one of the most basic
building blocks of current networks
– Without really understanding IP
numbers, Telecom Administrators can’t
deploy VoIP
– If the Telecom Administrator cannot
deploy VoIP, it will be turned over to the
IT department
Avaya Certification
Communications Networking test:
Given the IP number 207.174.21.156, with a subnet
mask of 255.255.255.192, find:
a)
b)
c)
The number of hosts in the subnet
The network address
The broadcast address
What is an IP Number?
– An IP Number identifies a host
(computer or phone) on a subnet, just
like an extension identifies a phone on
a cabinet
– IP configuration has 3 parts:
IP Number –
192.168.1.1
Subnet Mask –
255.255.255.0
Gateway –
192.168.1.254
– What? Why 3 parts?
Phone Talk
• Telephones talk to each other on
dedicated wires
• Ports are connected dedicated
physical ports
• How do computers find each other
to talk?
Computer Talk
• Computers talk to other computers
in two ways.
Broadcast
Routing
Inside Subnet - Broadcast
– Recipient is
determined as inside
– Message is sent to
all computers
– The intended
recipient listens
– Other computers
ignore the message
Outside Subnet - Routed
– Recipient determined
as outside
– Message broadcast to
local Gateway (router)
– Gateway forwards
message to destination
subnet
– Message is broadcast
to final destination
IP Configuration – 3 Parts
• IP Configuration includes the
host identifier (computer,
phone, router, etc)
• IP Configuration includes a
‘subnet mask’ to show which
destinations are inside and
which are outside their
subnet (broadcast vs
routing)
• IP Configuration includes a
gateway to reach all
destinations outside the
subnet
192.168.1.1
255.255.255.0
192.168.1.254
Dwight’s College Diploma
The blank space above is an accurate depiction of what
was inside Dwight’s diploma case at graduation time.
Bits and Bytes
– Computers store things in binary,
either a zero or a one.
– A single zero or one is a bit. 8 zeros or
ones are a byte.
IP Numbers
– An IP number is made up of 32 bits,
divided into four groups of 8 (four bytes).
11000000 10101000 00000001 00000001
IP Numbers for Humans
– Since humans don’t usually speak binary,
we use the decimal system
– Each byte (or octect) is written as a
decimal number ranging from 0 to 255
– The decimal numbers are separated by
periods, or dots
11000000101010000000000100000001
192.
168.
1.
1
Binary Math – Really Easy
• Binary math is based on powers of 2, as
opposed to powers of 10 for decimal
math.
– Decimal math has a 1s place, 10s place, 100s
place, etc…
– Binary math has a 1s place, 2s place, 4s
place, 8s place, etc…
128
bit 1
64
bit 2
Most significant bit
32
bit 3
16
8
4
2
bit 4
bit 5
bit 6
bit 7
1
bit 8
Least significant bit
Binary Math to Decimal
• When a bit is 0 its value is zero
• When a bit is 1, its value is its place value
• The total is the decimal value (the one we use)
– 11000000 = 128 + 64 = 192
– 10101000 = 128 + 32 + 8 = 168
– 11111111 = 128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 255
128
bit 1
64
bit 2
Most significant bit
32
bit 3
16
8
4
2
bit 4
bit 5
bit 6
bit 7
1
bit 8
Least significant bit
Binary-Decimal Translation
11000000101010000000000100000001
192.
168.
1.
1
11000000 = 128 + 64 = 192
10101000 = 128 + 32 + 8 = 168
00000001 = 1
00000001 = 1
128
bit 1
64
bit 2
Most significant bit
32
bit 3
16
8
4
2
bit 4
bit 5
bit 6
bit 7
1
bit 8
Least significant bit
Birthday Bytes
Dwight is 00100111 years old
Broadcast vs Routing
• All computers reside in a subnet – ie, a
portion of the larger network
• Computers choose broadcast or routing
by deciding whether their destination is
inside their subnet or outside of their
subnet
• The subnet mask defines which is
which, but how?
Subnet Masks (ie, Area Codes)
• An IP Address is divided into two
components
– The Network bits, or ‘outside part’
– The Host bits, or ‘inside part’
– This is kind of like area codes / DID blocks
32-bit IP Address
Network bits
Host Bits
Subnet Mask
mask [mæsk], Noun
- a covering to disguise or conceal
the face
- cover with a sauce;
"mask the meat“
- Block out, divide
into parts
Subnet Mask Secrets
– The subnet mask overlays the IP
number
– ones are network bits, zeros are
host bits
IP Number
11000000 10101000 00000001 00000001
Subnet Mask
11111111 11111111 11111111 00000000
Again, with Numbers
– The subnet mask overlays the IP
number
– ones are network bits, zeros are
host bits (this is a 24 bit subnet)
IP Number
192 . 168 .
1
.
1
11000000 10101000 00000001 00000001
Subnet Mask
255 . 255 .
255 .
0
11111111 11111111 11111111 00000000
Bigger Subnets
– The subnet mask overlays the IP
number
– ones are network bits, zeros are
host bits (this is a 16 bit subnet)
IP Number
192 . 168 .
1
.
1
11000000 10101000 00000001 00000001
Subnet Mask
255 . 255 .
0
.
0
11111111 11111111 00000000 00000000
The Network Remains
– The network bits of an IP number
are the same for all hosts within a
subnet.
– The host bits change for each host
– Host bits range from all zeros to
all ones
Hosts in a 24 bit Subnet
– The network bits stay the same
– The host bits change for each host
First Host IP
192 . 168 .
1
.
0
11000000 10101000 00000001 00000000
Last Host IP
192 . 168 .
1
. 255
11000000 10101000 00000001 11111111
Subnet Mask
255 . 255 .
255 .
0
11111111 11111111 11111111 00000000
Questions
• Note to self – stop here to see if
you have totally confused people,
because the really hard part is
coming next
Subnet Size
• Subnet masks that match to octets
are easy to work with
– 255.255.255.0 Class C
– 255.255.0.0
Class B
– 255.0.0.0
Class A
• Subnet masks that match to octets
are not very efficient (256 hosts
jumps to 65534!)
Variable Length Subnet Masks
• What about making things more
efficient by allowing subnets to be
defined at any point in the 32 bit IP
number?
• Aka Classless
Inter Domain
Routing or
C I D R!
Valid Subnet Masks
• Subnet masks use zeros and
ones to divide the IP number
into network bits and host bits.
11111111 11111111 11111111 00000000
OK!
11111111 11111111 00000000 00000000
OK!
11111111 11111111 11110001 00011000
NO!
Dividing at Octects is Easy
– The subnet mask overlays the IP number
– Each decimal number is either part of
the network, or part of the host
IP Number
192 . 168 .
1
. 193
11000000 10101000 00000001 11000001
Subnet Mask
255 . 255 .
255 .
0
11111111 11111111 11111111 00000000
VLSM can divide Anywhere!
– The subnet mask overlays the IP number
– A decimal number can be a combination
of network and host bits!
0+1
IP Number
192 . 168 .
1
.
1
11000000 10101000 00000001 00000001
Subnet Mask
255 . 255 .
255 . 128
11111111 11111111 11111111 10000000
VLSM can divide Anywhere!
– The subnet mask overlays the IP number
– A decimal number can be a combination
of network and host bits!
128 + (64+1)
IP Number
192 . 168 .
1
. 193
11000000 10101000 00000001 11000001
Subnet Mask
255 . 255 .
255 . 128
11111111 11111111 11111111 10000000
VLSM Subnets
• The network bits remain the same for all
hosts in the subnet
• Subnets are not required to start at the
decimal number zero
• A single decimal range (0-255) can be
split into multiple subnets
VLSM – 25 bit Subnet
– The last decimal number is split into two
subnets
– This is because the 25th bit can be a zero or a
one
Subnet A
192 . 168 .
1
.
0-127
11000000 10101000 00000001 0 - - - - - - -
Subnet B
192 . 168 .
1
. 128-255
11000000 10101000 00000001 1 - - - - - - -
Subnet Mask
255 . 255 .
255 . 128
11111111 11111111 11111111 1 0000000
VLSM – 26 bit Subnet
– The last decimal number is split into four
subnets
– This is because the 25th and 26th bit can form
four combinations of zeros and ones
Subnet A
192 . 168 .
1
.
0-63
11000000 10101000 00000001 00 - - - - - -
Subnet B
192 . 168 .
1
.
64-127
11000000 10101000 00000001 01 - - - - - -
Subnet C
192 . 168 .
1
.
128-191
11000000 10101000 00000001 10 - - - - - -
Subnet D
192 . 168 .
1
.
192-255
11000000 10101000 00000001 11 - - - - - -
Subnet Mask
255 . 255 .
255 . 192
11111111 11111111 11111111 11 000000
VLSM / CIDR Notation
– Network administrators sometimes
save time by including the subnet
mask as a slash (/) and then the
number of network bits
192.168.1.1 / 26
Subnet - Reserved Hosts
– The lowest number in a subnet (host bits
all zeros) is called the network address
– The highest number in a subnet (host bits
all ones) is called the broadcast address
– The available host addresses are all the
remaining combinations of the host bits.
255.255.255.0 Subnet
Network bits
Network
Address
110000001010100000000001 00000000
192.
First Host
Address
1.
0
168.
1.
1
110000001010100000000001 11111110
192.
Broadcast
Address
168.
110000001010100000000001 00000001
192.
Last Host
Address
Host bits
168.
1.
254
110000001010100000000001 11111111
192.
168.
1.
255
Questions
• Note to self, stop
here to let the
smoke from the
blown up brains
disperse a little
Broadway Suites - Current
1942 Broadway
LEGEND
SM Fiber (LX)
MM Fiber (50 micron SX)
1919 14th
(Vectra Bank)
1300 Walnut
Randolph
1800 Broadway
1801 13th
1301 Canyon
VoIP Value Adds
• Ease of deployment
• Future ready technology
• Low up front deployment cost
Broadway Suites - Future
• Migrate analog devices
(fax, modem) to IP
• Converged networks
• Unified Communications
• Extreme Networks
Binary Math Joke
There are only 10 kinds of people in
this world – those who understand
binary math and those who don’t