Based on SIP protocol community health network system design

With social progress and scientific and technological development, as well as people's quality of life continue to improve, community health care (Community Health Care, CHC) has become the focus of medical research in the area.

Community Healthcare refers to community residents of this community in the implementation of care diagnosis, treatment, rehabilitation and health care, namely the establishment of community-based telemedicine network. Modern multimedia technology and digital communications technology to the rapid development of the implementation of the Community Healthcare provides the technology foundation. Community health services is internationally recognized as an ideal model of primary health services, community health services in health policy, which is our country's health system reform. Under current community health services, Ministry of health has proposed the development of community health service's overall goals: 2000 basic complete pilot community health services and the expansion of the pilot, in 2005 the basic set up in various parts of the community health service systems frame, 2010 in the establishment of a complete community health service system. Almost all the developed industrial countries have established remote medical system to help healthcare services to meet the growing needs of the public. Now the United States has more than 8 000 community clinics and medical institutions for patients with chronic diseases and the elderly of telemedicine services.

As the next-generation network technology, softswitch and not only will the public switched telephone network and PSTN (Public Switched Telephone Network and PSTN) migrate to IP networks, VoIP (Voice over Internet Protocol, VoIP), he applied to the telecommunications carriers provide an excellent architecture, voice service, video business, emerging Internet business into a unified framework, SIP protocol is one of the key link.

The youngest by IETF working groups, one of the SIP working group published SIP related standards have become the communication and research network community. Current SIP working group published a draft of the agreement and has more than 30, in addition to the core protocol, other agreements cover QoS, security, message headers, and extend, and PSTN, and other Protocol interoperability, pass through the firewall and NAT, application number of the message body, instant messaging, and many other topics, with the ultimate goal is successful for all Internet applications provide ubiquitous access, contact the Internet and telecommunications, multimedia and important medium.

This article in accordance with the country vigorously develop the overall principles and community medicine and Shandong province information industry special development fund project "virtual hospital integrated platform of research and development" project needs, through the community health clinic and home healthcare needs deep human research and analysis, comprehensive utilization of electronic technology, computer technology and modern communication technology, and design a based on SIP protocol for patients with chronic diseases and the elderly of the community of remote monitoring network system.

The system as a hospital and a bridge between the patients and reduce unnecessary "patient access hospital" and the number of patients with a doctor's prescription, achieving more effective and high-quality patient care, the patient's stay at home as much as possible to accept the College's medical guidance and care measures. In Jinan City, a community trial run of results showed the feasibility of a system design and the advanced nature.

1 SIP architecture

SIP is an application-layer Control Protocol, and HTTP, SIP is a communications protocol, is a series of standards for the collection.

He defines the terminal device (computer, fixed telephone and mobile phone) to exchange information by agreement.

SIP can create, modify, and terminate multimedia sessions or calls.

SIP has 2 kinds of structure elements, that is, the user agent UA and network servers. UA is located in the SIP terminal station, he has two parts: first, the user agent client (UAC), are responsible for issuing the SIP request; the second is the user agent server (UAS), is responsible for responding to SIP requests. And in General, the two parts can be converted. Among them, the user agent server are 3 barrier type, namely: redirect servers, proxy servers and registration server (Register).

SIP network architecture diagram shown in Figure 1.

As a user agent Server 3 types of redirection server by sending the caller access to the URL address of the SIP INVITE message processing.

Proxy server performs application layer routing SIP requests and responses. Proxy server can be a memory or no memory of. A memory of proxy are processed after a call, will completely forget about all the information about the call until the next message to arrive. In addition, the agent can be a branch of the agent, which may also be no branch agency, for example, there are several branch agent enables simultaneous ring, phone until someone picks up where 1 phone, and no branch agency once only a telephone ring. Registration server is typically used to record the SIP address (SIP URL) and the associated IP addresses are commonly used to start the registration. Due to the use of SIP REGISTER message URL address when the INVITE request arrives, proxy or redirect server can be directly forwarded request information. This is based on the registered servers forwarding properties make up the network support real number mobility services. Typically, a SIP network server enables access to the type of server combination. SIP call typical process, as shown in Figure 2.

Figure 2, user@sipl.com as UAC, want to speak with user2@sip2.com, UAC first send an INVITE request, the local SIP proxy sipl.com receive this INVITE request, address resolution, send it to a SIP proxy server sip2.corn while sip1.co

M return to User1 a 100 Trying messages. Sip2.com receives the INVITE request sip1.com, forward it to user2@sip2.com and returns a message to sip1.com Trying. User2 receives the INVITE request, the response will be returned to the sip2.com a 180 Ringing Ringing message, this message will be forwarded to turn, User1 sip1.com. If User2 decided to answer the call, it returns a 200 OK message, this message after sip2.com, sip1.com, finally got User1. User1 receive 200 OK message, send an ACK confirmation message to User2. This call setup process is complete, User1 and User2 media channels can be established between the dialogue. If a party wants to end a call, sending a BYE message to each other, the other party returns a 200 OK message, SIP call is terminated.

Community based telemedicine system uses the SIP protocol as the key agreement for the design of the system is based on the design aspects of the Internet in medicine there is a clear advantage:

(1) SIP has superior scalability, can greatly reduce the central node (core network server), so that the system service.

(2) using the SIP protocol you can easy ways to embed the cheap end user devices and ensures their interoperability, so that different devices to communicate.

(3) SIP multi-party Conference emphasized support, including IP multicast and request features, this branch for remote consultation provides a very good support.

2 system design and implementation

SIP protocol in the network video monitoring, Web conferencing, VoIP and other fields have more successful applications.

Using SIP application in these areas, the successful experiences in this community of SIP-based remote network system uses a personal computer-based, computer communication network for technology platform, modular design, the first phase of the project the main framework for monitoring ECG, blood pressure and other physiological parameters, and can be remote consultation of the monitoring network for patients in the community can get doctors or specialists in the care treatment, rehabilitation, medical management and medical services. The system has a modular design, you can target different chronic diseases and the elderly care requirements provide different services.

2.1 system hardware components and connections

The community of telemedicine systems from a user's terminal equipment (home of cameras, personal computers, medical Terminal), community medical electronic workstation, community health records database, etc.

Use of hospital and community-wide already have computer network systems, system software installation to use. System uses the C/S structure, is divided into client and business logic middle-tier and server-side. From the content is divided into user information management, personal health records management, information management and consultation of a doctor. The system consists of a database server, community clinics, server a client, family, clients, and user interface file system, install the system differentiates between Community client and family clients respectively will automatically install the required documents and complete the appropriate settings. Each communication from random start customer process initiated by the server process from the post is on standby, ready to respond to the client process, thereby meeting the monitoring requirements.

Community health systems hardware basic structure as shown in Figure 3.

Hardware design of the system, the need to establish a database server, using a large hard drive of the high-grade microcomputer, mainly hard disk storage capacity, in order to establish a patient databases, and storage of medical data, etc.

Install Windows NT Server, Server operating systems, as he provides a client/server mode, you can speed up the processing speed of the network. In the users and community clinics only need 1 computers and some simple monitoring, sampling equipment can make patients achieve the convenience of home medical treatment. In addition, for those suffering from a serious chronic disease patients and the elderly in their home equipment monitoring instruments, such as: for the blood glucose meters and diabetes mellitus; used for asthma peak flow meters; used for breathing the ECG heart disease; used for electronic sphygmomanometer patients with hypertension. At the same time, community clinics can also provide some for fetal and maternal care equipment, this community of pregnant family loan, and care for pregnant women in particular high-risk pregnancy pregnant women and fetuses have a very good help and guidance role. The database server can be placed in community clinics and community clinics server a client to share the same computers, through the Windows NT Server, the composite computer within the community is a small local area network, easy to manage.

2.2 software functionality modules and implementation

System software structure as shown in Figure 4.

The system's core software for a remote dynamic management platform.

Registration login module for community users and community physicians registered login, record basic information for patients and users of information management. Electronic medical records of patients ' previous module Diagnostics records, inspection results and treatment measures. Software and hardware interface module provides systems and telemedicine terminal data transfer, and you can set the appropriate parameters. Remote consultation Kit modules provide patients to doctors face-to-face consultation, while the doctor is also available through his patient's rehabilitation status have a Visual understanding.

System work flow diagram as shown in Figure 5.

System for the typical workflow: disease

People and doctors first login in the database, access to a user ID, login with ID number and password. Once you are logged in, the patient will be able to establish their own detailed health records, and can use some of your own home to get medical data to fill in the appropriate place, and then submit. Community physicians into the system, you can view the data in this community, patients and patient archives in measured medical diagnostic data asynchronously, and the diagnosis results written to patient medical records, then the system automatically reply to a patient's condition has been diagnosed. In addition, the system also provides remote consultation services to patients through the consultation appointment booking service and community doctors, at the appointed time for remote consultation for treatment. At present, the patient education is becoming an important component of the healthcare system, computer-based training courses delivered by medical platform, allowing the patient to become more efficient and effective. Here, the platform you can E-mail or BBS, some medical training materials available to the residents of this community.

3. conclusions and implications

Development of community-based remote monitoring network system of purpose and meaning lies in:

(1) shorten the doctors and patients, community clinics generally within each of the communities, community residents near the patient to provide timely assistance, reduction of patients and medical staff, the road trips.

In addition to the physiological parameters in patients with important Telemonitoring, paramedic, also in case of sudden deterioration in the police.

(2) the number ageing population in the community increases, on community health requirements are also getting higher and higher.

On self-care capability poor elderly people's everyday life for remote monitoring, not only can increase the level of care and health care professionals and patients quality of life, also can evaluate the health status of the monitor object.

(3) the level of modern life and lifestyle changes, with sincere in the cerebrovascular disease, diabetes, sleep syndrome, chronic diseases in the crowd growing.

For chronically ill patients for remote monitoring, not only the patient's current knowledge of their illnesses, and can be passed to the remote network to timely access to medical rehabilitation Guide.

(4) through community-based remote monitoring system, in the core of community clinics and hospitals to establish links between the mutual exchange of patient's electronic medical record and for remote consultation, not only achieved a "referral", but also to a certain extent reduce core large hospital for medical treatment, the pressure to achieve a "shunt" patients.

As mentioned above, build a community of telemedicine network platform that not only improves the existing medical facilities and medical professionals work efficiency and work quality, ease the shortage of medical conditions and requirements for the medical care of the contradiction between, and to a certain extent, can network a lot of health information resources through the computer networks that provide community residents to achieve health education.

System although little peripheral hardware support, many features from the software alternative, but currently the community conditions also is not very balanced, therefore also need to design according to the specific situation in line with current community conditions module into the system, allowing the system to be further improved.

Modern medical care industry's long-term trend is towards networked intelligent medical systems, the building of a people-oriented and innovative health care system, through community-based health care networks continues to improve, to the progressive realization of the "little disease in the community, the disease went to the hospital" good medical situation.

Through community and family, community and major hospitals together medical system will become fully utilize health care resources, reduce medical costs, achieving good medical model.