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Configuring TCP/IP on a Windows NT Computer
Published in Steven F. Blanding, Enterprise Operations Management, 2020
The subnet mask represents a sequence of set bits that is logically ANDed with the IP address to determine the extended network address. Because the first or first two bit positions of an IP address indicates the type of address, it also indicates the length of the network portion of the address prior to subnetting. By subtracting the length of the IP address from the ANDed length, the device can determine the length of the subnet portion of the address and the value in the subnet portion. For example, the subnet mask of 255.255.255.0 shown in Exhibit 28.2 when ANDed with the IP address of 205.131.175.97 results in a 24-bit address. However, because the network address of 205.131.175.0 represents a Class C address that consists of a 3-byte network address and 1-byte host address, this indicates that no subnetting occurred. Thus, a subnet mask of 255.255.255.0 represents a nonsubnetted Class C address. Similarly, a subnet mask of 255.255.0 would indicate a nonsubnetted Class B address, while a subnet mask of 255.0.0.0 would represent a nonsubnetted Class A network address.
Internetworking
Published in Jerry D. Gibson, The Communications Handbook, 2018
tools, performing a cost-performance breakeven analysis, and developing link configurations. Network management: The third component of the network design process, which encompasses management of configuration, faults, performance, accounting, and security. Equipment and network software is acquired, verified, installed, maintained, and administered. Packet burst: A sliding window implementation that allows transmitting multiple packets and receiving a multiple packet acknowledgment, greatly improving the efficiency of SPX/IPX internetworking. Subnet mask: A four octet field used to identify the link portion of an IP address by setting bits to 1 where the network is to treat the corresponding bit in the IP address as part of the network address. Total network engineering process: A process to engineer and optimize internetworks including the three phases of awareness, design, and management, with a feedback control mechanism, progressing toward a network optimum.
OSI and TCP/IP Reference Models
Published in James Aweya, Designing Switch/Routers, 2023
In addition to other characteristics, the Network Layer (Layer 3) defines the network addresses, which are logical addresses, and are different from MAC addresses as discussed above. Logical addresses, like IP addresses, are organized as a hierarchy (using a hierarchical address space) and are not hard-coded on devices. A network address is typically based on where a device is in a particular network segment (IP subnet or VLAN), or on logical groupings of network devices that have no particular physical basis. The Network Layer controls the logical addressing of devices, and defines the logical network layout, to allow routers (which are Layer 3 devices) to use this information to determine how to route packets in the network.
Virtualised Environment for Learning SDN-based Networking
Published in IETE Journal of Education, 2020
Oscar Polanco, Fabio G. Guerrero
The principle proposed by SDN for the control plane has been identified by the ITU as an important concept to be extended to user and management planes. This concept, which is called “softwarization,” is a part of the requirements identified for IMT-2020 systems (International Mobile Telecommunications) by study group 13 [5]. Network functions virtualisation (NFV),[6] decouples network functions such as routing, firewall, intrusion detection, and NAT (Network Address Translation) from proprietary hardware platforms, and implements them in software. It uses standard virtualisation technologies that run on high-performance common hardware (non-proprietary) to virtualise network functions. NFV is applicable to any processing in the data plane or to any function in the control plane, in both wired and wireless network infrastructures. NFV has several features in common with SDN because they share the following objectives: moving functions to a software, using common hardware platforms instead of proprietary platforms, using APIs, and more efficiently supporting the implementation of network functions. In addition, SDN and NFV are independent but complementary schemes. In order to make a clear distinction between SDN and NFV, it should be noted that SDN decouples data and control planes, making the control and routing of network traffic more flexible and efficient. In contrast, NFV decouples the network functions from the specific hardware platforms through virtualisation, and provides these functions by using generic hardware platforms.
Development of building thermal environment emulator to evaluate the performance of the HVAC system operation
Published in Journal of Building Performance Simulation, 2019
To remotely evaluate the operation, it is useful for the emulator system to be able to communicate using the BACnet/IP, which requires specification of the network addresses of the BACnet devices. Each network address is given as a four-octet IP address followed by a two-octet UDP port number. Normally, 47808 (“xBAC0” in hexadecimal) is used as the port number, which is identified by the IP address. However, when multiple BACnet devices are virtually coexistent within a single software package such as an emulator, assigning different IP addresses is difficult, in which case it is permissible to identify the BACnet device by making the port number unique (ASHRAE 2016). The IP addresses of the approximately 100 BACnet devices included in the proposed emulator are equivalent to those of the computer on which the emulator runs and are identified by the port number.