Why is classful addressing considered waste?

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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 IP addresses 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 waste of IP addresses.



Now coming to my question. Don't all computers in a company reside behind a public IP address configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as the public IP address. All the computers in that office would have 192.168.xxx.xxx as private IP addresses. The same for other offices. I could use 20 different public IP addresses for other offices spreading around the world and have same private IP addresses behind a routers.



Doesn't this mean I could have many offices with networks with only Class C allocation?










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    up vote
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    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 IP addresses 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 waste of IP addresses.



    Now coming to my question. Don't all computers in a company reside behind a public IP address configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as the public IP address. All the computers in that office would have 192.168.xxx.xxx as private IP addresses. The same for other offices. I could use 20 different public IP addresses for other offices spreading around the world and have same private IP addresses behind a routers.



    Doesn't this mean I could have many offices with networks with only Class C allocation?










    share|improve this question









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      up vote
      3
      down vote

      favorite









      up vote
      3
      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 IP addresses 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 waste of IP addresses.



      Now coming to my question. Don't all computers in a company reside behind a public IP address configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as the public IP address. All the computers in that office would have 192.168.xxx.xxx as private IP addresses. The same for other offices. I could use 20 different public IP addresses for other offices spreading around the world and have same private IP addresses behind a routers.



      Doesn't this mean I could have many offices with networks with only Class C allocation?










      share|improve this question









      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 IP addresses 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 waste of IP addresses.



      Now coming to my question. Don't all computers in a company reside behind a public IP address configured by a router? Let's say I have one router for an office in Istanbul which has 185.245.32.78 as the public IP address. All the computers in that office would have 192.168.xxx.xxx as private IP addresses. The same for other offices. I could use 20 different public IP addresses for other offices spreading around the world and have same private IP addresses behind a routers.



      Doesn't this mean I could have many offices with networks with only Class C allocation?







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      edited 18 mins ago









      Peter Mortensen

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      1395






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      asked 18 hours ago









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          5 Answers
          5






          active

          oldest

          votes

















          up vote
          4
          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.






          share|improve this answer



























            up vote
            5
            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.






            share|improve this answer






















            • 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
              4 hours ago

















            up vote
            4
            down vote













            You bring up several different topics in one question 😏. Let me address them separately.



            First, understand that classful 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.



            You’re describing 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 - it's 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.






            share|improve this answer





























              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.






              share|improve this answer




















              • 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
                4 hours ago


















              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 address. 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 the old days there were offices where every device had a public IP address (I managed such a net 16-18 years ago). It had some advantages and some disadvantages.



              Another reason why offices aren't important in this regard: Simple offices often only need the IP address they get from their ISP, meaning they don't even affect the allocation the company might have.






              share|improve this answer










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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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                5 Answers
                5






                active

                oldest

                votes








                5 Answers
                5






                active

                oldest

                votes









                active

                oldest

                votes






                active

                oldest

                votes








                up vote
                4
                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.






                share|improve this answer
























                  up vote
                  4
                  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.






                  share|improve this answer






















                    up vote
                    4
                    down vote



                    accepted







                    up vote
                    4
                    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.






                    share|improve this answer












                    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.







                    share|improve this answer












                    share|improve this answer



                    share|improve this answer










                    answered 18 hours ago









                    Ron Maupin♦

                    56.3k94695




                    56.3k94695




















                        up vote
                        5
                        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.






                        share|improve this answer






















                        • 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
                          4 hours ago














                        up vote
                        5
                        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.






                        share|improve this answer






















                        • 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
                          4 hours ago












                        up vote
                        5
                        down vote










                        up vote
                        5
                        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.






                        share|improve this answer














                        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.







                        share|improve this answer














                        share|improve this answer



                        share|improve this answer








                        edited 6 hours ago

























                        answered 18 hours ago









                        Zac67

                        19.4k21047




                        19.4k21047











                        • 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
                          4 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
                          4 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
                        4 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
                        4 hours ago










                        up vote
                        4
                        down vote













                        You bring up several different topics in one question 😏. Let me address them separately.



                        First, understand that classful 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.



                        You’re describing 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 - it's 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.






                        share|improve this answer


























                          up vote
                          4
                          down vote













                          You bring up several different topics in one question 😏. Let me address them separately.



                          First, understand that classful 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.



                          You’re describing 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 - it's 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.






                          share|improve this answer
























                            up vote
                            4
                            down vote










                            up vote
                            4
                            down vote









                            You bring up several different topics in one question 😏. Let me address them separately.



                            First, understand that classful 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.



                            You’re describing 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 - it's 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.






                            share|improve this answer














                            You bring up several different topics in one question 😏. Let me address them separately.



                            First, understand that classful 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.



                            You’re describing 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 - it's 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.







                            share|improve this answer














                            share|improve this answer



                            share|improve this answer








                            edited 15 mins ago









                            Peter Mortensen

                            1395




                            1395










                            answered 18 hours ago









                            Ron Trunk

                            31.6k22667




                            31.6k22667




















                                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.






                                share|improve this answer




















                                • 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
                                  4 hours ago















                                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.






                                share|improve this answer




















                                • 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
                                  4 hours ago













                                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.






                                share|improve this answer













                                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.







                                share|improve this answer












                                share|improve this answer



                                share|improve this answer










                                answered 11 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
                                  4 hours 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
                                  4 hours 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
                                4 hours 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
                                4 hours ago











                                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 address. 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 the old days there were offices where every device had a public IP address (I managed such a net 16-18 years ago). It had some advantages and some disadvantages.



                                Another reason why offices aren't important in this regard: Simple offices often only need the IP address they get from their ISP, meaning they don't even affect the allocation the company might have.






                                share|improve this answer










                                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.





















                                  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 address. 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 the old days there were offices where every device had a public IP address (I managed such a net 16-18 years ago). It had some advantages and some disadvantages.



                                  Another reason why offices aren't important in this regard: Simple offices often only need the IP address they get from their ISP, meaning they don't even affect the allocation the company might have.






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                                    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 address. 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 the old days there were offices where every device had a public IP address (I managed such a net 16-18 years ago). It had some advantages and some disadvantages.



                                    Another reason why offices aren't important in this regard: Simple offices often only need the IP address they get from their ISP, meaning they don't even affect the allocation the company might have.






                                    share|improve this answer










                                    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 address. 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 the old days there were offices where every device had a public IP address (I managed such a net 16-18 years ago). It had some advantages and some disadvantages.



                                    Another reason why offices aren't important in this regard: Simple offices often only need the IP address they get from their ISP, meaning they don't even affect the allocation the company might have.







                                    share|improve this answer










                                    New contributor




                                    Henrik is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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                                    edited 15 mins ago









                                    Peter Mortensen

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                                    answered 16 hours ago









                                    Henrik

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                                    1011




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