Timely exchange of information within team members is an important component of the successful work of any company, regardless of its specifics and scale. The spread of digital technologies in all industries contributes to the widespread implementation of corporate networks in different levels business, from small firms to holdings.
Design and construction of a corporate network
The popularity of corporate networks is due to a number of their advantages.
Reduced system downtime in case of hardware, software and technical errors assumes a stable, continuous exchange of data between all participants.
Special programs and fine-tuning of access rights to individual documents, functions and sections reduce the risk of information leakage and loss of confidential data. In addition, violators are easy to track using software solutions.
The process of designing a corporate network includes the unification of local networks of departments within the company and the creation of a material and technical base for further planning, organization and management of the core activities of the enterprise.
The construction of a corporate network is based on an agreed and developed architecture of data, platforms and applications, through which information is exchanged between users. Obtaining a functioning corporate network additionally involves the development of database maintenance and protection tools.
Companies creating corporate networks
Among the companies creating corporate networks, it is worth noting:
- Altegra Sky is a Moscow company engaged in providing a full range of services related to the creation of an internal network, from drawing up the fundamental architecture to commissioning. The company purchases, installs, commissions all necessary equipment and conducts training events for its clients.
- Universum is a Moscow-based provider of system integration services and the creation of secure local networks for wide-ranging enterprises. Specialization - installation and fine-tuning of all functional elements of local networks and ensuring uninterrupted operation.
- Open Technologies is a provider of innovative solutions for data exchange within the company. The company's specialization is the creation of an optimal hierarchical structure that will ensure consistently high speed of transfer of documents, images and multimedia using the available server capacity.
Structure, architecture, technologies of enterprise corporate networks
The corporate network of an enterprise is characterized by two elements. LAN is a local area network that provides stable exchange of necessary data and management of user access rights. To create it you need hardware- structured cable networks, hereinafter referred to as SCS. SCS is a telecommunications infrastructure - a collection of all computer devices companies between which data exchange occurs in real time.
Creating a corporate network consists of choosing:
- working group;
- modeling environments;
- software and hardware solutions for its creation;
- configuration and maintenance of the finished architecture.
Building an architecture and choosing a corporate network technology consists of several stages:
- selection of elementary objects included in the corporate data exchange network. As a rule, these are certain products, services of the company and information on them;
- selection of functional, information and resource models for the future network. At this stage, the “internal logic” of the functioning of the future network is determined;
- further, based on the already selected parameters, languages and modeling methods are determined that can solve the assigned problems.
For example, when forming a corporate network for a small manufacturing company, the most accessible modeling languages that do not require hardware power are used. Conversely, creating an architecture for large companies with a wide profile of activities involves the use of powerful tools.
Corporate local networks via VPN and Wi-Fi
VPN, or Virtual Private Network - creation option virtual network within an enterprise that uses the capabilities of the global network. The peculiarity of building such a network is the ability to access the Internet from anywhere in the world using a registered login and password. The solution is popular among IT companies, design bureaus and other enterprises that hire employees for remote work. The disadvantage of this method of organization local network- threat of unauthorized access and loss of user data.
Wi-Fi is a more technologically advanced and modern option for creating a corporate network that is not tied to hardware capacity and the physical location of users. Using routers, network access is configured for all employees, and you can “get” into the network from any device. The main advantage of Wi-Fi is easy integration and scaling of the created network for any number of users. WITH using Wi-Fi dynamic redistribution of network bandwidth is carried out between individual nodes, depending on the level of applied load.
Corporate satellite network
Operation of this type a corporate local network is built on the use of the power of a HUB - a satellite terminal located in network control centers. Each participant accesses the network using an IP address and a relay satellite that transmits a signal to other users.
This option for organizing a corporate network allows you to:
- quickly connect new users to the existing network;
- remotely monitor its functioning and compliance by participants with the security policy;
- guarantee data safety and fine-tuned privacy.
Satellite networks are the most stable, expensive and technologically advanced way to organize data exchange between employees of the same structure.
Corporate multiservice network
A feature of a multiservice network is the ability to transmit text, graphic, video and audio information using the same communication channels. As a rule, companies providing services for building multiservice networks create turnkey solutions that allow all necessary types of information to be transmitted via IP addresses.
In technical terms, separate subsystems are created that are designed to transmit certain types of information, while switches, routers and signal amplifiers are used to transmit data. Thus, the network is more stable, tolerates high load levels well and allows peripheral devices to access the central server as quickly as possible.
Corporate computer network
A computer network within a company is an adaptation of Internet technologies for use at the level of an individual company. The main purpose of building such networks is the joint use of information for internal corporate work: simultaneous access and editing of documents, data exchange.
The functioning of a computer network involves the use operating system compatible with all equipment and software connected to it. It is important to ensure rational distribution of information and provide employees with tools for planning and document management.
The stage of building the architecture of a corporate computer network involves constant communication with future users in order to identify their needs. A successfully built corporate computer network is a convenient software and hardware solution for use in daily work.
Corporate social network
Creating a tool for transmitting messages and exchanging information within one company gives employees the opportunity to maintain contact between departments in real time. At the same time, the product is based on the principle of operation of ordinary social networks with “reduced” functionality, which does not distract the attention of employees from their professional duties.
Typically, access to corporate social network have company employees who are in the office or working remotely, while confidential work issues are discussed using secure communication protocols. This ensures prompt and secure communication between company departments without interrupting production and without the threat of data leakage.
Remote access to the corporate network
basis remote access One of the capabilities of a corporate network is setting up the VPN protocol, which ensures the use of company servers by running a virtual machine.
The technology is based on a terminal server, free subnets and a secure guest network. There is no need for the user to purchase or configure additional programs: access via VPN is carried out in the “Team Viewer” application, compatible with all versions of Windows OS.
This solution is safe due to the possibility fine tuning access rights to data stored on company servers.
Security of corporate networks: threats and protection
Unauthorized access to data stored on corporate servers and the threat of their loss are two main dangers from which it is necessary to protect the enterprise network.
For these purposes the following are used:
- antivirus systems;
- operational blocking unauthorized access manually;
- thin VPN setup networks that cut off unauthorized users by entering a login and password.
Constant protection is carried out using firewalls that monitor the functioning of all network elements in real time.
SCPC technology
A time-tested, two-way solution satellite internet are duplex SCPC channels created in a point-to-point manner.
The fairly high price per subscriber node does not allow the construction of regional networks using this technology. Duplex SCPC channels are used by relatively large providers in the absence of terrestrial channels or as a backup channel.
Technologies for VSAT networks with a star structure
Today the market offers a number of network technologies with various methods access (TDMA, DAMA, FTDMA) to the space segment. As a rule, they have a star-type structure. The network has a central station with a large-radius antenna, which combines the functions of a gateway to external networks and a control center, as well as user terminals with small-sized antennas.
The remote subscriber terminal has the following characteristics: reception up to 16 Mbit/s, return channel - up to 1 Mbit/s, the ability to organize telephony and fax transmission.
Selecting a technical solution when designing a corporate network using satellite communications
When designing a corporate network, it is advisable to select a technical solution in three stages:
- choice of technology (TDM/TDMA, SCPC, MF-TDMA or others..)
- selection of relay satellite;
- choosing a specific system among those available on the market.
Today, there are several basic technologies for building satellite communication networks. They all have their advantages and disadvantages, but none of them are universal. To improve operational efficiency in many modern systems several technologies are successfully combined at the same time. The main difference between them is the way the satellite repeater resource is used. Let's take a look at these technologies.
SCPC(Single Channel Per Carrier) / MCPC (Mult Channel Per Carrier) are actively used to build small networks with intense traffic. Each ground station implementing SCPC has a dedicated permanent segment of satellite transponder capacity and supports permanent connection. The main advantage of this technology is that it guarantees the necessary throughput of the satellite communication channel, and the main disadvantage is the lack of the ability to dynamically redistribute the repeater resource between network nodes.
DAMA(Demand Assigned Multiple Access) provides satellite repeater resource on demand. In networks with DAMA technology, a communication channel is allocated to the user only for the duration of the communication session, which significantly saves the resources of the satellite repeater. Some implementations of DAMA technology provide the ability to establish connections with different bandwidths for different communication sessions. The repeater resource is distributed by the central station of the network.
MF-TDMA(Multi-Frequency-Time Division Multiple Access) provides multiple stations with dynamic access to a common time division channel. Unlike DAMA technology, access is provided much faster. However, TDMA ground stations are quite expensive because each of them - even with minimal traffic - must transmit data at a rate equal to the total capacity of the time-distributed channel. In TDMA networks, there is usually no central control station.
FTDMA(Frequency Time Division Multiple Access) is a technology for networks with different topologies (mesh or star), which is selected depending on the type of main traffic (telephony or data transfer). In an FTDMA network, a central ground station organizes communications for remote stations by providing them with free time slots on several carrier frequencies.
TDM/TDMA(Time Division Multiplexing / Time Division Multiple Access) - a combined technology of networks with a star topology. The central ground station communicates with user stations via one or more assigned TDM (time-multiplexed) channels, and the user stations access the central ground station via TDMA channels. In a TDM/TDMA network, data transmitted between any two user stations passes through the relay satellite twice (“double hop”). In this case, a significant (1-2 s) signal delay occurs.
When choosing a particular technology, input data such as the number of terminals in the network, functionality, and communication channel capacity are taken into account (see table).
When choosing a satellite, the following parameters should be taken into account: the cost of renting a space segment, the energy parameters of the transponder and its coverage area. Selecting a specific system (technical equipment) is a rather complex process, since, despite the similarity of satellite communication systems from different manufacturers operating on the same technology, they are not identical and have many features that can greatly affect the investment and operational characteristics of the network being created.
More often corporate systems satellite communications are created on the principle of “everyone with everyone” or have a “star” structure. VSAT class satellite stations are installed in the company's remote offices. Network management and monitoring systems (NMS), usually installed at a central ground station, are used to configure and monitor the network. The main functions are redistribution of resources between users, management of remote stations, monitoring the current state of network components. NMS tools ensure the collection and primary processing of statistical data about the network. Management and monitoring systems are built on the basis of SNMP agents installed on each remote terminal.
We offer prompt connection to the Internet of remote objects
Photo 1. Connecting the temporary construction headquarters to the Internet via two-way satellite channel Ka-Sat
We offer services for prompt connection to the Internet and telephone installation of facilities in the Moscow region such as:
- Construction headquarters, construction trailers
- Change houses and temporary buildings
- Security trailers
- Warehouse field trailers
- Farms and field buildings
As well as any other objects scattered throughout the Moscow region and in need of connection with the central office.
Sunduchkov K. S., Kogut A. L., Sunegin D. G., Sushko S. I. Educational and Scientific Institute of Telecommunication Systems at NTUU "KPP" Industrial Lane. 2, Kiev, 03056, Ukraine
Abstract The work sets out the formulation of the problem of optimizing the architecture and parameters of a corporate satellite information transmission network.
I. Introduction
For small corporate satellite information transmission networks, the cost of equipment and operating costs become fundamental. The objective function of network optimization is to minimize these costs. The area for changing parameters is a field of various protocols for generating a digital stream and network management.
II. Main part
Existing corporate information transmission networks can be classified as Terrestrial networks, satellite networks, hybrid networks using both satellite and terrestrial channels. In addition, corporate networks differ in terms of coverage area, the number of subscribers served, the intensity and nature of traffic, the cost of equipment, the cost of operating expenses, etc.
To clarify the subject of this work, we will consider a small corporate network to be a satellite network that serves subscribers in the territory of Ukraine, numbering up to 15-20 subscribers, providing a limited range of services (telephone, fax, data transfer) and having a total traffic of up to 100 MB/day. The parameter of such a network is the “Corporate Satellite Network for Operational Monitoring of Wind Power Plants” (CSOM WPP).
Composition of KSSOM
KSSOM consists of subscriber transceiver stations (USTS) and a central transceiver station (CPTS) at the receiving center in
KSSOM is built on a modular principle. One module provides for servicing 6 departments, two modules 12, etc. Expansion to 24, 48, 96, etc. is provided.
The APPS consists of a mini-VSAT transceiver terminal and a subscriber terminal (AT).
The central station consists of a mini-VSAT, a central terminal (CT) with a network management system and related software.
AT and CT personal computer with a modulator and demodulator, an installed program to ensure the information exchange technology used.
Terminal composition:
For transmission, modulator, interface, buffering, scrambling, noise-resistant coding, modulation and pre-filtering circuits, reference oscillator;
For reception, demodulator, interface, main selection path, Viterbi decoder, descrambler, buffer, reference oscillator;
At the customer's request, KSSOM is equipped with cryptographic protection equipment.
Expected technical and economic parameters of KSSOM
APPS and DSPS receivers must ensure reception of a signal with a bit error probability of no more than 3-10′ 6 for at least 99.53% of the worst month.
Full service life of at least 10 years.
Shelf life 12 years.
The cost of operating expenses for one branch, the cost of supplying equipment for one set as well as the number of subscribers in the network, traffic and information speeds of channels are the subject of the contract.
Warranty service 1 year, post-warranty service under a separate agreement. The solution to the problem of reducing operating costs and, first of all, the cost of renting a satellite resource, the cost of renting a HUB station, seems to us in the following directions: minimizing the operating frequency band of the leased satellite resource; refusal to lease traditional HUB stations in favor of development specialized program network management; renting out unused corporate network resources to other corporations.
To implement the above, optimization problems are solved software formation of a digital stream, creation of a specialized network management system. The field on which the optimal protocols are searched consists of: “Protocol X.25” (CCITTRecomendatio X.25), FR with the addition of LMI, IP (Internet Protocol), etc.
Preliminary calculations show that the total operating frequency band leased on the satellite can be 64 kHz (duplex channel 2x32 kHz). At the same time, the operating costs for renting a satellite resource at a cost of $4000 per 1 MHz per month is $256 per month. If the cost of this rental is divided by 20 subscribers, then the cost of the resource on the satellite for one subscriber will be = $128 per month.
III. Conclusion
A two-level architecture of a satellite information transmission network is proposed, in which all subscribers have access to SCPS network resources upon request. FR digital stream generation protocol. Bandwidth (frequency resource on the transponder) 64 kHz. The transmission frequency is up around 14 GHz, down 12 GHz. The network has up to 20 directions, connected via satellite to the Information Processing Center in Kyiv.
The network option we offer is based on domestically produced terminals. This provides the following advantages: lower supply costs of terminals, cheaper terms of contracts for warranty and post-warranty service. In addition, this solution provides additional jobs for domestic producers.
1. Sunduchkov K. S., Steklov V. K. Technologies and stations of satellite networks built according to the “star” scheme. Tutorial K.: SE UNIIS, 2001, 67 p.
2. Sunduchkov K. S., Steklov V. K. Control in satellite communication networks built according to the “everyone with everyone” scheme. Textbook K.: SE UNIIS, 2001, 33 p.
3. Sunduchkov K. S., Steklov V. K. Structure of the frequency-time plan of the decentralized satellite communication network “SNT VX-VSAT”. Study guide K.:
SE UNIIS, 2001 -36 p.
4. Makarov A. A., Sunduchkov K. S. “System for operational monitoring of wind farms.” Reports III International conference“Unconventional energy in the 21st century” National Academy of Sciences of Ukraine, Institute of Technical Thermophysics, Crimea, Sudak, September 9-15, pp. 119-121.
SMALL CORPORATE SATELLITE NETWORK FOR DATA TRANSMISSION
Sunduchkov K. S., Kogut A. L, Sunegin D. G., Sushko S. I.
Research Institute of Telecommunications, National Technical University of Ukraine ‘Kyiv Polytechnical Institute’
2 Industrialnyy Provulok, Kyiv, Ukraine, 03056
Abstract The architecture and parameter optimization of a corporate satellite data transmission network are analyzed in the present paper.
Hardware costs and operational expenses are critical for small corporate satellite data transmission networks. The primary objective for optimization is the minimization of these costs. The parameter variation range includes various digital streaming and network management protocols.
The existing corporate data transmission networks could be divided into terrestrial networks, satellite networks and hybrid networks that use satellite and terrestrial links. In addition, corporate networks differ in territory coverage, number of subscribers, traffic intensity, hardware costs, etc.
Let us assume that a small network is a satellite-based network servicing subscribers located in the territory of Ukraine, with the number of subscribers below 15-20 and offering a limited number of services (phone, fax, data transmission). The daily traffic for a small corporate satellite network should not exceed 100Mb. An example of such network could be found in
As “Corporate satellite network of real-time wind power station monitoring” (CSNRWPSM).
The CSNRWPSM includes subscriber receiver and transmitter stations (SRTS) and a central receiver and transmitter station (CRTS) located at a receiver station in Kiev, Ukraine.
The CSNRWPSM is set up using the modular approach. A single module serves 6 sections, two modules 12, etc. 24, 48, 96, etc., sections could be built up in this way.
The SRTS comprises a transceiver terminal of a mini-VSAT type and a subscriber terminal.
The CRTS consists of a mini-VSAT, a central terminal with a network management system and appropriate software.
The subscriber and central terminals are PCs equipped with modulators and demodulators and supported by software to provide the operation of a chosen data exchange technology.
The transmitter portion of the terminal includes modulator; interface; buffering, scrambling, antinoise coding, modulation and pre-filtering circuits; reference oscillator.
The receiver portion of the terminal includes demodulator; interface; main gating path; Viterbi decoder; descrambler; buffer; reference oscillator.
On subscriber’s request an encryption protection circuit may be installed with the CSNRWPSM.
The expected CSNRWPSM parameters are as follows:
The SRTS and CRTS receivers should provide for a
signal reception with a BER below 3-1 O’ 6 for at least 99.53% ofthe worst month.
Total service life exceeding 10 years.
Storage time 12 years.
Operational expenses per one section, costs of a single unit of equipment, number of subscribers per network, traffic and data link rates are subject to agreement.
Warranty service is provided for one year, subsequent servicing is subject to agreement. Cutting operational costs may be achieved along the following lines: minimization of the rented satellite channel bandwidth, using in-house network management software instead of traditional HUB-station lease, leasing unused frequency resources.
Preliminary estimates show that the overall rented satellite bandwidth could be 64kHz (2*32kHz duplex channel). Wth the leasing fees at $4000 a month per 1MHz, the costs of renting satellite resources would be $256 a month. Divided between 20 subscribers, the costs for each subscriber would be $12.8 a month.
A two-level architecture of the corporate satellite data transmission network is presented. All subscribers are granted an on-demand access to the network resources. The digital streaming protocol is Frame Relay. The bandwidth (transponder frequency resource) is 64kHz. The uplink frequency is in the 14GHz range, downlink about 12GHz. The network comprises up to 20 directions connected via the satellite with the Data Processing Center in Kyiv, Ukraine.
The proposed network utilizes terminals manufactured in Ukraine. This offers the benefits of purchasing terminals at lower costs, as well as cheaper warranty and post-warranty servicing. It also creates additional jobs for the home economy.
