Mixing
Why Classful Addressing Is Considered As Wasting
Clash Royale CLAN TAG#URR8PPP
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I am trying to understand the addressing strategies. But there is something which I can't grasp. Maybe I am missing a very basic point, if so, I am sorry beforehand.
From my researches, let's say, if a company wants 100,000 IPs for their network, Class C won't cut it since Class C can allocate 256 addresses. Same for Class B since it can allocate 65,536 addresses. So they were asking for Class A which can allocate 16,777,216 addresses but that would be a huge wastage of IPs.
Now coming to my question. Don't all computers in a company reside behind a public IP configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as public IP. All the computers in that office would have 192.168.xxx.xxx as private IPs. Same for other offices. I could use 20 different public IPs for other offices spreading around the world and have same private IPs behind a routers.
Doesn't this mean I could have many offices with networks with only Class C allocation?
ip network
asked 15 hours ago
HalilM
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up vote
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I am trying to understand the addressing strategies. But there is something which I can't grasp. Maybe I am missing a very basic point, if so, I am sorry beforehand.
From my researches, let's say, if a company wants 100,000 IPs for their network, Class C won't cut it since Class C can allocate 256 addresses. Same for Class B since it can allocate 65,536 addresses. So they were asking for Class A which can allocate 16,777,216 addresses but that would be a huge wastage of IPs.
Now coming to my question. Don't all computers in a company reside behind a public IP configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as public IP. All the computers in that office would have 192.168.xxx.xxx as private IPs. Same for other offices. I could use 20 different public IPs for other offices spreading around the world and have same private IPs behind a routers.
Doesn't this mean I could have many offices with networks with only Class C allocation?
ip network
asked 15 hours ago
HalilM
82
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HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
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up vote
1
down vote
favorite
up vote
1
down vote
favorite
I am trying to understand the addressing strategies. But there is something which I can't grasp. Maybe I am missing a very basic point, if so, I am sorry beforehand.
From my researches, let's say, if a company wants 100,000 IPs for their network, Class C won't cut it since Class C can allocate 256 addresses. Same for Class B since it can allocate 65,536 addresses. So they were asking for Class A which can allocate 16,777,216 addresses but that would be a huge wastage of IPs.
Now coming to my question. Don't all computers in a company reside behind a public IP configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as public IP. All the computers in that office would have 192.168.xxx.xxx as private IPs. Same for other offices. I could use 20 different public IPs for other offices spreading around the world and have same private IPs behind a routers.
Doesn't this mean I could have many offices with networks with only Class C allocation?
ip network
asked 15 hours ago
HalilM
82
New contributor
HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I am trying to understand the addressing strategies. But there is something which I can't grasp. Maybe I am missing a very basic point, if so, I am sorry beforehand.
From my researches, let's say, if a company wants 100,000 IPs for their network, Class C won't cut it since Class C can allocate 256 addresses. Same for Class B since it can allocate 65,536 addresses. So they were asking for Class A which can allocate 16,777,216 addresses but that would be a huge wastage of IPs.
Now coming to my question. Don't all computers in a company reside behind a public IP configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as public IP. All the computers in that office would have 192.168.xxx.xxx as private IPs. Same for other offices. I could use 20 different public IPs for other offices spreading around the world and have same private IPs behind a routers.
Doesn't this mean I could have many offices with networks with only Class C allocation?
ip network
ip network
asked 15 hours ago
HalilM
82
New contributor
HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 15 hours ago
HalilM
82
New contributor
HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 15 hours ago
HalilM
82
New contributor
HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 15 hours ago
HalilM
82
asked 15 hours ago
HalilM
82
82
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HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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New contributor
HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
HalilM is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
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5 Answers
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active
oldest
votes
up vote
3
down vote
accepted
You are confusing the typical home networking setup, which is off-topic here. with a business network. Many businesses have multiple services (often the same type of service provided by different servers), and they need public addressing for each server.
Under your example, a company with multiple web servers for different functions would have a single public address, and TCP port 80 (HTTP) for that single public address could only be forwarded to one of those servers.
The original premise of IP is that each host gets a unique address. The version of NAT (NAPT) that allows a network to hide behind a single public address only works with ICMP, TCP, and UDP. Other transport protocols are broken by NAPT, and even some application-layer protocols that use TCP or UDP are broken by NAPT.
answered 15 hours ago
Ron Maupin♦
56.2k94695
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up vote
4
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You bring up several different topics in one question ðŸ˜Â. Let me address them separately.
First, understand that classfull addressing is obsolete, and has been since before you were born. I don’t know why they still teach it, but it’s ancient history.
Second, what you say is theoretically possible, but that’s not the way the Internet works.
What you’re describing is Network Address Translation (NAT) which was developed to get around the lack of IPv4 addresses. You use private addresses inside your network and translate them to one or more public addresses. Typically those public addresses belong to your ISP who “rents†them to you.
You can get “your own†address space, but only if you’re a large organization- its also expensive.
Internet service providers do not advertise networks smaller than /24 on the internet, so your public addresses for all your offices will be part of your ISP addresses. If you have your own , you can’t advertise anything less than /24 or a block of 256 addresses.
answered 15 hours ago
Ron Trunk
31.6k22667
add a comment |Â
up vote
4
down vote
Network classes died 25 years ago when CIDR was introduced in 1993.
Classes were extremely wasteful because end user requirements needed to be rounded up to the next largest class. A requirement for 1,000 IP addresses was allocated a class B network, removing 65,536 addresses from the pool. That's a "waste" of 98%.
You can hide a lot of private IP addresses behind a single public address (or just a few addresses) if you just need client access. However, if you're planning to offer services to the public Internet you do need proper, public IPs.
Note that NAT was only defined in 1999, six years after CIDR. Without NAT, HTTP and other application-layer proxies need be used to provide private-to-public connectivity. Both NAT and proxies break the end-to-end paradigm of TCP/IP and can cause serious problems.
answered 15 hours ago
Zac67
19.3k21047
The general problem is of course exactly as you say. But I certainly remember allocations of multiple class C blocks rather than a class B long before CIDR was universal, though of course this had impact on size of routing tables.
– jonathanjo
2 hours ago
add a comment |Â
up vote
0
down vote
If you're taking some kind of course where they teach you about network classes, you'll probably need to remember that stuff until you've passed. Apart from that: Forget about network classes, it hasn't been relevant for 25 years.
You're right in saying that simple offices don't need more than one public ip. But the internet contains both non-simple offices (the company I work for used to host test servers in our office in Copenhagen that had to be accessible to employees in Dubai) and networks that aren't offices.
And in old days there were offices where every devices had a public ip (I managed such a net 16-18 years ago), it had some advantages and some disadvantages.
An another reason why offices aren't important in this regard: Simple offices often only need the IP they get from their ISP, meaning they don't even affect the allocation the company might have.
answered 13 hours ago
Henrik
1011
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Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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up vote
0
down vote
Don't all computers in a company reside behind a public IP configured by a router?
This is a set-up which became "normal" in the 1990s - maybe after the end of classful routing in 1993 or at the same time.
Before that time NAT was at least not common so each computer in the internet had its own public IP address!
So a company with 260 computers needed 260 public IP addresses.
With classless routing this actually means 512 public IP addresses; with classful routing this means 65536 public IP addresses.
answered 8 hours ago
Martin Rosenau
4375
Depending on regional addressing policies at a particular time, a 260 requirement might well have had two class C blocks allocated. "Public IP address" was the only kind before RFC 1597 in 1994 (ignoring loopback etc).
– jonathanjo
1 hour ago
add a comment |Â
5 Answers
5
active
oldest
votes
5 Answers
5
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
3
down vote
accepted
You are confusing the typical home networking setup, which is off-topic here. with a business network. Many businesses have multiple services (often the same type of service provided by different servers), and they need public addressing for each server.
Under your example, a company with multiple web servers for different functions would have a single public address, and TCP port 80 (HTTP) for that single public address could only be forwarded to one of those servers.
The original premise of IP is that each host gets a unique address. The version of NAT (NAPT) that allows a network to hide behind a single public address only works with ICMP, TCP, and UDP. Other transport protocols are broken by NAPT, and even some application-layer protocols that use TCP or UDP are broken by NAPT.
answered 15 hours ago
Ron Maupin♦
56.2k94695
add a comment |Â
up vote
3
down vote
accepted
You are confusing the typical home networking setup, which is off-topic here. with a business network. Many businesses have multiple services (often the same type of service provided by different servers), and they need public addressing for each server.
Under your example, a company with multiple web servers for different functions would have a single public address, and TCP port 80 (HTTP) for that single public address could only be forwarded to one of those servers.
The original premise of IP is that each host gets a unique address. The version of NAT (NAPT) that allows a network to hide behind a single public address only works with ICMP, TCP, and UDP. Other transport protocols are broken by NAPT, and even some application-layer protocols that use TCP or UDP are broken by NAPT.
answered 15 hours ago
Ron Maupin♦
56.2k94695
add a comment |Â
up vote
3
down vote
accepted
up vote
3
down vote
accepted
You are confusing the typical home networking setup, which is off-topic here. with a business network. Many businesses have multiple services (often the same type of service provided by different servers), and they need public addressing for each server.
Under your example, a company with multiple web servers for different functions would have a single public address, and TCP port 80 (HTTP) for that single public address could only be forwarded to one of those servers.
The original premise of IP is that each host gets a unique address. The version of NAT (NAPT) that allows a network to hide behind a single public address only works with ICMP, TCP, and UDP. Other transport protocols are broken by NAPT, and even some application-layer protocols that use TCP or UDP are broken by NAPT.
answered 15 hours ago
Ron Maupin♦
56.2k94695
You are confusing the typical home networking setup, which is off-topic here. with a business network. Many businesses have multiple services (often the same type of service provided by different servers), and they need public addressing for each server.
Under your example, a company with multiple web servers for different functions would have a single public address, and TCP port 80 (HTTP) for that single public address could only be forwarded to one of those servers.
The original premise of IP is that each host gets a unique address. The version of NAT (NAPT) that allows a network to hide behind a single public address only works with ICMP, TCP, and UDP. Other transport protocols are broken by NAPT, and even some application-layer protocols that use TCP or UDP are broken by NAPT.
answered 15 hours ago
Ron Maupin♦
56.2k94695
answered 15 hours ago
Ron Maupin♦
56.2k94695
answered 15 hours ago
Ron Maupin♦
56.2k94695
answered 15 hours ago
Ron Maupin♦
56.2k94695
56.2k94695
add a comment |Â
add a comment |Â
up vote
4
down vote
You bring up several different topics in one question ðŸ˜Â. Let me address them separately.
First, understand that classfull addressing is obsolete, and has been since before you were born. I don’t know why they still teach it, but it’s ancient history.
Second, what you say is theoretically possible, but that’s not the way the Internet works.
What you’re describing is Network Address Translation (NAT) which was developed to get around the lack of IPv4 addresses. You use private addresses inside your network and translate them to one or more public addresses. Typically those public addresses belong to your ISP who “rents†them to you.
You can get “your own†address space, but only if you’re a large organization- its also expensive.
Internet service providers do not advertise networks smaller than /24 on the internet, so your public addresses for all your offices will be part of your ISP addresses. If you have your own , you can’t advertise anything less than /24 or a block of 256 addresses.
answered 15 hours ago
Ron Trunk
31.6k22667
add a comment |Â
up vote
4
down vote
You bring up several different topics in one question ðŸ˜Â. Let me address them separately.
First, understand that classfull addressing is obsolete, and has been since before you were born. I don’t know why they still teach it, but it’s ancient history.
Second, what you say is theoretically possible, but that’s not the way the Internet works.
What you’re describing is Network Address Translation (NAT) which was developed to get around the lack of IPv4 addresses. You use private addresses inside your network and translate them to one or more public addresses. Typically those public addresses belong to your ISP who “rents†them to you.
You can get “your own†address space, but only if you’re a large organization- its also expensive.
Internet service providers do not advertise networks smaller than /24 on the internet, so your public addresses for all your offices will be part of your ISP addresses. If you have your own , you can’t advertise anything less than /24 or a block of 256 addresses.
answered 15 hours ago
Ron Trunk
31.6k22667
add a comment |Â
up vote
4
down vote
up vote
4
down vote
You bring up several different topics in one question ðŸ˜Â. Let me address them separately.
First, understand that classfull addressing is obsolete, and has been since before you were born. I don’t know why they still teach it, but it’s ancient history.
Second, what you say is theoretically possible, but that’s not the way the Internet works.
What you’re describing is Network Address Translation (NAT) which was developed to get around the lack of IPv4 addresses. You use private addresses inside your network and translate them to one or more public addresses. Typically those public addresses belong to your ISP who “rents†them to you.
You can get “your own†address space, but only if you’re a large organization- its also expensive.
Internet service providers do not advertise networks smaller than /24 on the internet, so your public addresses for all your offices will be part of your ISP addresses. If you have your own , you can’t advertise anything less than /24 or a block of 256 addresses.
answered 15 hours ago
Ron Trunk
31.6k22667
You bring up several different topics in one question ðŸ˜Â. Let me address them separately.
First, understand that classfull addressing is obsolete, and has been since before you were born. I don’t know why they still teach it, but it’s ancient history.
Second, what you say is theoretically possible, but that’s not the way the Internet works.
What you’re describing is Network Address Translation (NAT) which was developed to get around the lack of IPv4 addresses. You use private addresses inside your network and translate them to one or more public addresses. Typically those public addresses belong to your ISP who “rents†them to you.
You can get “your own†address space, but only if you’re a large organization- its also expensive.
Internet service providers do not advertise networks smaller than /24 on the internet, so your public addresses for all your offices will be part of your ISP addresses. If you have your own , you can’t advertise anything less than /24 or a block of 256 addresses.
answered 15 hours ago
Ron Trunk
31.6k22667
answered 15 hours ago
Ron Trunk
31.6k22667
answered 15 hours ago
Ron Trunk
31.6k22667
answered 15 hours ago
Ron Trunk
31.6k22667
31.6k22667
add a comment |Â
add a comment |Â
up vote
4
down vote
Network classes died 25 years ago when CIDR was introduced in 1993.
Classes were extremely wasteful because end user requirements needed to be rounded up to the next largest class. A requirement for 1,000 IP addresses was allocated a class B network, removing 65,536 addresses from the pool. That's a "waste" of 98%.
You can hide a lot of private IP addresses behind a single public address (or just a few addresses) if you just need client access. However, if you're planning to offer services to the public Internet you do need proper, public IPs.
Note that NAT was only defined in 1999, six years after CIDR. Without NAT, HTTP and other application-layer proxies need be used to provide private-to-public connectivity. Both NAT and proxies break the end-to-end paradigm of TCP/IP and can cause serious problems.
answered 15 hours ago
Zac67
19.3k21047
The general problem is of course exactly as you say. But I certainly remember allocations of multiple class C blocks rather than a class B long before CIDR was universal, though of course this had impact on size of routing tables.
– jonathanjo
2 hours ago
add a comment |Â
up vote
4
down vote
Network classes died 25 years ago when CIDR was introduced in 1993.
Classes were extremely wasteful because end user requirements needed to be rounded up to the next largest class. A requirement for 1,000 IP addresses was allocated a class B network, removing 65,536 addresses from the pool. That's a "waste" of 98%.
You can hide a lot of private IP addresses behind a single public address (or just a few addresses) if you just need client access. However, if you're planning to offer services to the public Internet you do need proper, public IPs.
Note that NAT was only defined in 1999, six years after CIDR. Without NAT, HTTP and other application-layer proxies need be used to provide private-to-public connectivity. Both NAT and proxies break the end-to-end paradigm of TCP/IP and can cause serious problems.
answered 15 hours ago
Zac67
19.3k21047
The general problem is of course exactly as you say. But I certainly remember allocations of multiple class C blocks rather than a class B long before CIDR was universal, though of course this had impact on size of routing tables.
– jonathanjo
2 hours ago
add a comment |Â
up vote
4
down vote
up vote
4
down vote
Network classes died 25 years ago when CIDR was introduced in 1993.
Classes were extremely wasteful because end user requirements needed to be rounded up to the next largest class. A requirement for 1,000 IP addresses was allocated a class B network, removing 65,536 addresses from the pool. That's a "waste" of 98%.
You can hide a lot of private IP addresses behind a single public address (or just a few addresses) if you just need client access. However, if you're planning to offer services to the public Internet you do need proper, public IPs.
Note that NAT was only defined in 1999, six years after CIDR. Without NAT, HTTP and other application-layer proxies need be used to provide private-to-public connectivity. Both NAT and proxies break the end-to-end paradigm of TCP/IP and can cause serious problems.
answered 15 hours ago
Zac67
19.3k21047
Network classes died 25 years ago when CIDR was introduced in 1993.
Classes were extremely wasteful because end user requirements needed to be rounded up to the next largest class. A requirement for 1,000 IP addresses was allocated a class B network, removing 65,536 addresses from the pool. That's a "waste" of 98%.
You can hide a lot of private IP addresses behind a single public address (or just a few addresses) if you just need client access. However, if you're planning to offer services to the public Internet you do need proper, public IPs.
Note that NAT was only defined in 1999, six years after CIDR. Without NAT, HTTP and other application-layer proxies need be used to provide private-to-public connectivity. Both NAT and proxies break the end-to-end paradigm of TCP/IP and can cause serious problems.
answered 15 hours ago
Zac67
19.3k21047
edited 3 hours ago
answered 15 hours ago
Zac67
19.3k21047
answered 15 hours ago
Zac67
19.3k21047
answered 15 hours ago
Zac67
19.3k21047
19.3k21047
The general problem is of course exactly as you say. But I certainly remember allocations of multiple class C blocks rather than a class B long before CIDR was universal, though of course this had impact on size of routing tables.
– jonathanjo
2 hours ago
add a comment |Â
The general problem is of course exactly as you say. But I certainly remember allocations of multiple class C blocks rather than a class B long before CIDR was universal, though of course this had impact on size of routing tables.
– jonathanjo
2 hours ago
The general problem is of course exactly as you say. But I certainly remember allocations of multiple class C blocks rather than a class B long before CIDR was universal, though of course this had impact on size of routing tables.
– jonathanjo
2 hours ago
The general problem is of course exactly as you say. But I certainly remember allocations of multiple class C blocks rather than a class B long before CIDR was universal, though of course this had impact on size of routing tables.
– jonathanjo
2 hours ago
add a comment |Â
up vote
0
down vote
If you're taking some kind of course where they teach you about network classes, you'll probably need to remember that stuff until you've passed. Apart from that: Forget about network classes, it hasn't been relevant for 25 years.
You're right in saying that simple offices don't need more than one public ip. But the internet contains both non-simple offices (the company I work for used to host test servers in our office in Copenhagen that had to be accessible to employees in Dubai) and networks that aren't offices.
And in old days there were offices where every devices had a public ip (I managed such a net 16-18 years ago), it had some advantages and some disadvantages.
An another reason why offices aren't important in this regard: Simple offices often only need the IP they get from their ISP, meaning they don't even affect the allocation the company might have.
answered 13 hours ago
Henrik
1011
New contributor
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |Â
up vote
0
down vote
If you're taking some kind of course where they teach you about network classes, you'll probably need to remember that stuff until you've passed. Apart from that: Forget about network classes, it hasn't been relevant for 25 years.
You're right in saying that simple offices don't need more than one public ip. But the internet contains both non-simple offices (the company I work for used to host test servers in our office in Copenhagen that had to be accessible to employees in Dubai) and networks that aren't offices.
And in old days there were offices where every devices had a public ip (I managed such a net 16-18 years ago), it had some advantages and some disadvantages.
An another reason why offices aren't important in this regard: Simple offices often only need the IP they get from their ISP, meaning they don't even affect the allocation the company might have.
answered 13 hours ago
Henrik
1011
New contributor
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |Â
up vote
0
down vote
up vote
0
down vote
If you're taking some kind of course where they teach you about network classes, you'll probably need to remember that stuff until you've passed. Apart from that: Forget about network classes, it hasn't been relevant for 25 years.
You're right in saying that simple offices don't need more than one public ip. But the internet contains both non-simple offices (the company I work for used to host test servers in our office in Copenhagen that had to be accessible to employees in Dubai) and networks that aren't offices.
And in old days there were offices where every devices had a public ip (I managed such a net 16-18 years ago), it had some advantages and some disadvantages.
An another reason why offices aren't important in this regard: Simple offices often only need the IP they get from their ISP, meaning they don't even affect the allocation the company might have.
answered 13 hours ago
Henrik
1011
New contributor
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
If you're taking some kind of course where they teach you about network classes, you'll probably need to remember that stuff until you've passed. Apart from that: Forget about network classes, it hasn't been relevant for 25 years.
You're right in saying that simple offices don't need more than one public ip. But the internet contains both non-simple offices (the company I work for used to host test servers in our office in Copenhagen that had to be accessible to employees in Dubai) and networks that aren't offices.
And in old days there were offices where every devices had a public ip (I managed such a net 16-18 years ago), it had some advantages and some disadvantages.
An another reason why offices aren't important in this regard: Simple offices often only need the IP they get from their ISP, meaning they don't even affect the allocation the company might have.
answered 13 hours ago
Henrik
1011
New contributor
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered 13 hours ago
Henrik
1011
New contributor
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered 13 hours ago
Henrik
1011
answered 13 hours ago
Henrik
1011
1011
New contributor
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |Â
add a comment |Â
up vote
0
down vote
Don't all computers in a company reside behind a public IP configured by a router?
This is a set-up which became "normal" in the 1990s - maybe after the end of classful routing in 1993 or at the same time.
Before that time NAT was at least not common so each computer in the internet had its own public IP address!
So a company with 260 computers needed 260 public IP addresses.
With classless routing this actually means 512 public IP addresses; with classful routing this means 65536 public IP addresses.
answered 8 hours ago
Martin Rosenau
4375
Depending on regional addressing policies at a particular time, a 260 requirement might well have had two class C blocks allocated. "Public IP address" was the only kind before RFC 1597 in 1994 (ignoring loopback etc).
– jonathanjo
1 hour ago
add a comment |Â
up vote
0
down vote
Don't all computers in a company reside behind a public IP configured by a router?
This is a set-up which became "normal" in the 1990s - maybe after the end of classful routing in 1993 or at the same time.
Before that time NAT was at least not common so each computer in the internet had its own public IP address!
So a company with 260 computers needed 260 public IP addresses.
With classless routing this actually means 512 public IP addresses; with classful routing this means 65536 public IP addresses.
answered 8 hours ago
Martin Rosenau
4375
Depending on regional addressing policies at a particular time, a 260 requirement might well have had two class C blocks allocated. "Public IP address" was the only kind before RFC 1597 in 1994 (ignoring loopback etc).
– jonathanjo
1 hour ago
add a comment |Â
up vote
0
down vote
up vote
0
down vote
Don't all computers in a company reside behind a public IP configured by a router?
This is a set-up which became "normal" in the 1990s - maybe after the end of classful routing in 1993 or at the same time.
Before that time NAT was at least not common so each computer in the internet had its own public IP address!
So a company with 260 computers needed 260 public IP addresses.
With classless routing this actually means 512 public IP addresses; with classful routing this means 65536 public IP addresses.
answered 8 hours ago
Martin Rosenau
4375
Don't all computers in a company reside behind a public IP configured by a router?
This is a set-up which became "normal" in the 1990s - maybe after the end of classful routing in 1993 or at the same time.
Before that time NAT was at least not common so each computer in the internet had its own public IP address!
So a company with 260 computers needed 260 public IP addresses.
With classless routing this actually means 512 public IP addresses; with classful routing this means 65536 public IP addresses.
answered 8 hours ago
Martin Rosenau
4375
answered 8 hours ago
Martin Rosenau
4375
answered 8 hours ago
Martin Rosenau
4375
answered 8 hours ago
Martin Rosenau
4375
4375
Depending on regional addressing policies at a particular time, a 260 requirement might well have had two class C blocks allocated. "Public IP address" was the only kind before RFC 1597 in 1994 (ignoring loopback etc).
– jonathanjo
1 hour ago
add a comment |Â
Depending on regional addressing policies at a particular time, a 260 requirement might well have had two class C blocks allocated. "Public IP address" was the only kind before RFC 1597 in 1994 (ignoring loopback etc).
– jonathanjo
1 hour ago
Depending on regional addressing policies at a particular time, a 260 requirement might well have had two class C blocks allocated. "Public IP address" was the only kind before RFC 1597 in 1994 (ignoring loopback etc).
– jonathanjo
1 hour ago
Depending on regional addressing policies at a particular time, a 260 requirement might well have had two class C blocks allocated. "Public IP address" was the only kind before RFC 1597 in 1994 (ignoring loopback etc).
– jonathanjo
1 hour ago
add a comment |Â
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