1 Introduction

Due to the procreation of information technology, today’s world is working in advanced networks, which include huge numbers of handheld gadgets with the ability to message broadcasting and data sharing in infrastructure-less mode. Tablets, mobiles, PDAs, smartphones, etc. are a few collections of handheld gadgets. Mobile Ad-hoc Networks (MANETs) are wireless networks, which include mobile nodes and work on a random topology [1,2,3]. The performance of MANET networks is directly proportional to the parameters like; linked among communicating nodes, message dropping, the routing protocol used during broadcasting the message, the traffic pattern of communication, etc. [4–5]. The few applications of MANETs are operations of military tactical, Androset, BOTNETs [6–7], search & rescue, disaster relief and for commercial use. After the advancement of the wireless network new network named the Opportunistic network was introduced by Kevin Fall in 2002 [8].

The OppNets works with the longer transmission delay among nodes with short-range communication areas according to the geographical proximity of mobile gadgets. For the dissemination of messages in OppNets, Bluetooth or Wi-Fi techniques are utilised. DTN/OppNet. network forwards the messages in a wireless network by using a Bundle Layer (BL). The sequence of adjacent data blocks is known as a bundle, it keeps the semantic information which permits the application to make progress in the network. These bundles are broadcast opportunistically in a store-carry-forward mechanism, whenever the opportunistic nodes come to their communicating range [9].

Many routing protocols were already introduced in OppNet. A description of a few protocols for an opportunistic network is Direct delivery: This protocol doesn’t create many copies of messages. Only the sender node directly transmits the packet to the receiver node. If the receiver node doesn’t receive the packet or if the sender node is not successful in sending the packet, either message will be discarded or destroyed, so in terms of delivery of the message this protocol is not reliable and efficient.

Epidemic Protocol: To save, the initial (original) message and the message for another node (work as a secondary buffer), two buffers are used by an epidemic routing protocol. For buffer management First-In-First-Out (FIFO) policy is applied. The first packet from the buffer is eliminated, whenever the buffer reaches its maximum capacity. By hop-count weightage and special 32-bit ID (identification number), messages in the buffer are categorized.

Spray and Wait Protocol: Transmission of replication of message packets is few as compared to epidemic protocol. Less delivery delay, negligible congestion and maximum scalability are provided by Spray and Wait for protocol. Cluster protocol: To update the online probability of contact is done by the EWMA (exponentially weighted movement average) scheme. Information transmission and routing in a network is done by gateways and clusters, which are selected by functions like join (), sync (), and leave () etc. Multiple very small size of clusters is formed, to avoid undefined errors. The objectives of this paper are as follows:

  1. (a)

    To provide the background of wireless networks; the taxonomy of wireless networks is discussed.

  2. (b)

    Bibliometrics assessment concerning wireless networks is encountered to give the information of highly contributed countries & authors, frequently used resources & keywords, and most cited authors.

  3. (c)

    Characteristics, strengths, weaknesses, and applications of a different wireless network are included in the article, which provides immense knowledge about various wireless networks to beginners.

This article is structured as; Taxonomy with the classification of wireless networks is presented in Sect. 2. The Bibliometrics assessment for wireless networks and their important outcomes is addressed in Sect. 3. Section 4, presents the properties, strengths, weaknesses, and applications of diverse networks. Section 5 presents the analysis of routing protocols which are used in different wireless networks. Finally, the conclusion of the paper is shown in Sect. 6.

2 Taxonomy of Wireless Network

This section describes the diversity of wireless networks. Wireless networks are categorized into single-hop and multi-hop-based networks with sub-diversion in infrastructure-based and infrastructure-less based as presented in Fig. 1. In single-hop communication in a network, the transmitted node directly sends the message to the receiver node without using a relay node or intermediate node. However, due to the larger communication area in a network, the sender node uses multi-hop communication, here relay node is used by the sender node to transmit the packet to the receiver node. The way through which, the network uses resources like; internet connectivity, operation of communication, required service in the network, access points, base stations, etc. is known as an infrastructure-based network. When the nodes in the network work.

Fig. 1
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Taxonomy of wireless network

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as a router and communicate without using any pre-defined infrastructure is known as an infrastructure-less network.

Wireless Local Area Networks (WLAN-802.11), Cellular Networks, and Wireless Metropolitan Area Networks (802.16) are examples of wireless network which exists in the category of a single-hop infrastructure-based wireless network. Bluetooth, Wi-Fi, WLAN-802.11, and Opportunistic networks lie in the class of single-hop infrastructure-less-based wireless networks. Contrasting classes of routing in OppNets are also shown in Fig. 1.

Wireless Sensor Network (WSN) is a multi-hop infrastructure-based wireless network. Here each sensor node, either keeps a radio trans-receiver with an in-built antenna or has a link to a microcontroller. WSN can work with both simple star topology and complicated multi-hop wireless mesh topology. Various categories of WSN routing techniques are shown in Fig. 1. Mobile Ad-hoc Networks (MANETs) and Vehicular Ad-hoc Networks (VANET) are examples of infrastructure-less based multi-hop wireless networks [10]. Existing routing protocols for MANET and VANET are also presented in Fig. 1.

3 Bibliometrics Analysis

Science mapping technique and performance analysis are integrated by the bibliometrics tool. Articles citation, network visualization, bibliographic coupling, co-occurrence of keywords, and co-occurrence of author citation network analysis are done by using the science mapping tool VOS viewer [11–12]. Diverse information like; sources from books & journals, no. of documents included, the average year of publication, average citation of the article, references, keywords, single-author papers, multi-author papers, and other information are included for wireless network bibliometrics analysis. The effective outcome of these 19 factors is presented in Table 1. This section is integrated with three subsections 3.1, 3.2, and 3.3.

Table 1 Main information for bibliometrics
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3.1 Article and Countries Bibliometrics Analysis

In this subsection “Article publication concerning years” from 1996 to 2022 and “Country citation of papers & average country citation of papers” are discussed. The Bibliometrics tool [11] and VOS viewer mapping tool are used to find all relevant data. The number of articles published from 1996 to 2022 in the domain of wireless networks is depicted in Fig. 2. A total of 1030 research articles were published, but 147 is the maximum number of articles published in 2015. The least number of papers 11 exist in the year 2004. From 2009 to 2015 approximately 71% of articles were published more as compared to 1996 to 2005.

Fig. 2
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Year-wise Number of Articles Published

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Productions of articles by diverse countries like; the USA, CHINA, INDIA, and others are included by the tool. The citation of the research paper produced by the country and the average citation of the article concerning the country is presented in Fig. 3. The USA is found as the top country which receives the maximum number of article citations (15,362) and Mexico is considered as a bottom country in terms of article citations (195). China is second (5357) and India is third (3887) in the top most countries in terms of article citations. India received 76% and 80% more citations as compared to Belgium and Italy respectively. 65% and 74% more citations are received by the USA as compared to China and India respectively.

Fig. 3
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Article citations & average article citation vs. country

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According to the average article citation concerning the country, Belgium is the top country (91.50) and France (8) is at the bottom. Belgium scored 89%, and 84% more average article citations as compared to Australia and India respectively. India received a 43% higher average article citation as compared to Korea. The USA received 76% and 64% more average article citations as compared to Iran and Turkey. The details of another country for the factor total citation and average total citation are presented in Fig. 3.

3.2 Citation Analysis of Author Keywords and Researchers

This sub-section discussed the author keyword citation and author citation network visualization. The graphical representation using the science mapping tool VOS viewer [11] is shown in Figs. 4 and 5.

Fig. 4
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Co-occurrence of author keyword citation

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During the bibliometrics analysis of wireless networks; approximately 9530 keywords were found but only, 4914 (40%) keywords were used by the researchers. Wireless Sensor Network, Routing, Quality of Services, Clustering, Load Balancing, and many other keywords are included by the tool; their co-occurrence of author keywords is shown in Fig. 4.

2000 research articles were encountered from 1996 to 2022. 4402 authors were included, out of which only 3% of authors are evaluated as single-author articles and 97% of articles are analysed as multi-authored. Figure 5 presents the visualization citation network for authors; colourful nodes are used to present different authors. According to the number of citations of a particular author; their node-size is varied. The large size of the author-node indicates, more citations of the author received and vice versa. The edges between colourful nodes show the collaborative work of the researchers; a greater number of edges shows a higher number of together articles.

Fig. 5
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Author’s citation network visualization

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3.3 Citation Analysis of Sources, Word Growth, and 3-D Plot

Article resources are the primary important input for bibliometrics analysis; the top 20 journals were encountered for wireless networks. Wireless networks, Transactions on Vehicular Networks, IEEE Communication Letters, IEEE Transactions on Networks, and other sources were found with their number of articles published as shown in Fig. 6. A total of 14,202 articles were published by these sources during 1992–2022.

Fig. 6
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Most cited sources

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Of the minimum number of articles (359), only 3% were produced by the “IEEE Communication Letters”. Wireless networks journal is evaluated as the top source to provide the number of articles (1399). “Transactions on Vehicular Networks” is the second journal which published 91% of the articles; it generates 13% fewer articles as compared to the “Wireless Networks” journal. “IEEE Transactions on Networks”, published 31.4%, and 67% more articles as compared to “Computer Networks”, and “IEEE Communication Letters” journals respectively.

From the bibliometrics analysis; word growth from the various articles was evaluated (1996–2022) and graphically presented in Fig. 7. Different keywords like; ad-hoc networks, energy efficiency, algorithms, sensor nodes, routing protocols, and others were analysed by using various colour waves. “Algorithm” word was evaluated as highly cumulate occurrences from 1996 to 2017 as compared to other keywords. “Wireless networks”, and “wireless sensor networks” found more word growth as compared to “algorithm” from 2018 to the present. “Energy efficiency”, and “Energy utilization” were considered as the least cumulate occurrences from 1996 to 2022.

Fig. 7
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Word growth used in wireless network

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The three-field plot for the factor’s authors, keywords, and effective sources from 1996 to 2022 is graphically represented in Fig. 8. Author, Keywords, and Source words are abbreviated as AU, DE, and SO respectively which are used in Fig. 8. Diverse authors (AU) like Kumar A, Wang D, Liu Y, Fang Y, and others are plotted first with different keywords (DE) used by researchers. More number of edges between AU and DE indicates a greater frequency of keywords used by authors. Different DE which used in various sources (SO) like wireless networks, ad-hoc and wireless sensor networks, and others are shown by waves in Fig. 8.

Fig. 8
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Three field plot author, keywords and sources

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4 Wireless Networks

In this section, diverse types of wireless networks like MANET, VANET, WSN, and OppNet are discussed with their important findings and outcomes. Significant features, strengths, weaknesses, and applications of these networks are summarized in Tables 2, 3, 4 and 5.

4.1 Mobile Ad-hoc Network (MANET)

Dynamic, self-organising, infrastructure-less, multi-hop based, and self-managing mobility nodes in the wireless network are known as MANET. In this, mobile gadgets can change their location from one place to another at any time. This network provides communication directly among nodes according to their transmission range. Mobile nodes in MANET are linked wirelessly [1–2, 5]. For the successful dissemination of messages in the network, relay nodes must cooperate [13–14].

Table 2 Details of MANET’s
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4.2 Vehicular Ad-hoc Network (VANET)

The concept of setting up the topology of vehicles for the same type of application and situation of use is known as VANET [15–16]. This is a highly efficient and reliable network, which is used to interlink vehicles in the environment like urban cities or highways. Base stations are used in VANET, for dissemination of the information in the network, where vehicles are used as independent nodes [17].

Table 3 Details of VANET’s
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4.3 Wireless Sensor Network (WSN)

The collection of hundreds or thousands of sensor nodes is known as Wireless Sensor Network. Radio, power, processing, and sensing units are the primary parts of each sensor node. This network works efficiently in a smaller area. Atmosphere pressure, temperature, humidity, etc. parameters are sensed by the sensor node. This information is disseminated to the destination node or sink node in WSN [18].

Table 4 Details of WSN’s
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4.4 Opportunistic Network (OppNet)

The improvement in MANET wireless network with tolerance in the delay is known as OppNet. Whenever the node gets the opportunity to disseminate the message in the network, the procedure of message transmission has occurred. This opportunity is depending on the working range of nodes in the network. By using the intermediate node or relay node in a network, the source node forwards the packet to the destination node successfully by using the store-carry-forward procedure during routing [8–9].

Table 5 Details of OppNet
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5 Analysis of Wireless Protocols

This section provides the empirical evaluation of diverse types of concepts used in wireless networks. This section is divided into two sections; it includes a theoretical analysis of wireless protocols.

5.1 Wireless Protocols Analysis

Figure 9 depicts the number of existing routing protocols of the MANET wireless network concerning different types of concepts used during the designing of that protocol. Key-based protocol was proposed in [1], symmetric key, asymmetric key, and group key-based are the primary categories of MANET protocol. Approx. 14 protocol was in the key management-based class. DKPS, PKIE, and INF protocols are in the subclass of symmetric key-based. SRP, URSA,

Fig. 9
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Protocols of mobile Ad-hoc network

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SOKM, Z&H, ID-C, etc. exist in the sub-category of the asymmetric-key-based protocol. SEGK was based on the category of group-key management scheme [21–22]. Around 20 routing protocols were introduced in the class of trust-based protocols in MANET. ABED, GRE, lies in the sub-category of protocol-based trust schemes of MANET. WATCHDOG, PATHRATER, CONFIDENT, CORE, etc. were proposed protocols in system-level-based trust protocol [23–24]. 24 routing protocols were lies in reactive, proactive, and hybrid-based. The three categories topology-based, key-based, and trust-based routing protocols are highlighted with green, blue, and orange colours respectively.

Figs. 10 and 11 describe the number of protocols for VANET and WSN respectively. Approximately 40 routing protocols were proposed in the VANET. Diverse classes like topology-based reactive, proactive, hybrid, cluster, geographic, and data fusion-based concepts were introduced in this type of network. Sub-class proactive routing protocols in VANET include PBR, DSDV, and OLSR. AID, FLUTE, SADV, HFED, MDD, NDMR, PRAODV, etc., protocols exist in reactive routing protocols. A-STAR, GPCR, GYTAR, RIVER, and GeoSVR come in the category of geographic-based routing schemes in VANET. Integration of geographic and topology concepts produces hybrid routing protocols; a few examples are HLAR, LAGAD, ZRP, etc. The cluster-based category includes LORA_CBR, FTLocVSDP, C-VANET, LEAPER, etc. routing protocols. DDFP, FCMA, D-SEMA, etc., are examples of data fusion-based routing protocols in VANET [17].

Fig. 10
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Protocols of vehicular Ad-hoc network

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Figure 11 presents various existing routing protocols in WSN. Security, flat, and location-based are different categories of protocols. SPINS, LKHW, LHA-SP, SERP, SMRP, BEARP, SR3, etc., are examples of security-based VANET protocols. Location-based WSNs include GAF, GEAR, TBFT, etc., and protocols lie in this category. QoS category includes SPEED, EAR, and SAR routing protocols. Approx. 60 routing protocols were included in WSN [25].

Fig. 11
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Protocols of wireless sensor network

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Diverse types of opportunistic routing protocols are presented in Fig. 12. Sub-class cryptography included privacy in context-based and epidemic forwarding, and bootstrapping security associations in opportunistic networks [26–27]. Non-cryptography-based opportunistic routing class includes trust in the opportunistic network, social trust in the opportunistic network, and trust management scheme based on behaviour feedback for the opportunistic network [28,29,30]. Realization of Incentives to Combat Selfishness, Incentives and Reputation for Opportunistic Networks using Social Networks, Socially Selfish Aware Routing, Incentive-based pub/sub, Barter Trade, etc., come in the class of incentive-based secure routing protocol [31,32,33].

Fig. 12
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Protocols of opportunistic network

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Various trust-based routing protocols were proposed in this category SUCCESS, RADON, and A trust-based framework for data forwarding [34], etc. Around 85 routing protocols in the opportunistic network were studied in this study. Routing for OppNet. exists in link-state aware classes are OR, ECONOMY, MORE, Code OR, Slide OR, etc. The geographical category includes CBF, GeRaF, GOR, MGOR, ROMER, etc. routing protocols. MaxPreps, FPOR, EBR, OPF, delegation forwarding, etc., are examples of probabilistic-based opportunistic routing protocols.

PHY-Aware ILOR, SPOR, EEPOR, TLGOR, Parallel OR, etc., are existing protocols in cross-layer routing protocols in the opportunistic network. The optimised-based category includes Graph-based SMAF, MABF, PLASMA, LOR, MAP, etc., routing protocols [9, 20, 35,36,37,38,39]. Figure 13 presents the analysis of existing routing protocols in the wireless network. A maximum ratio of existing protocols comes in the category of an Opportunistic network, and a minimum ratio is considered in the vehicular ad-hoc network.

Fig. 13
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Analysis of existing protocols in wireless network

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6 Conclusion, Limitations and Future Work

Due to advancements in technology, wireless networks apply to multidivergent environments. In this study, diverse kinds of existing routing protocols are described. A concept used during the design of the protocol is discovered. Taxonomy was discussed to give background knowledge of the wireless network. Bibliometrics analysis of wireless networks by using the science mapping tool VOS viewer was shown in figure-2 to figure-8. Articles published on “Wireless Network” concerning years, citations of articles concerning countries, and highly cited keywords & sources used by authors, were empirically analysed to find the most suitable, source, keyword and other information which are useful for researchers.

Their benefits, weaknesses, properties, and applications were presented effectively (in tabular form) for MANET, VANET, WSN, and OppNet in this paper. Approximately 14% of routing protocols come under the category VANET. 25% of routing protocols exist in the MANET and WSN. A maximum of 36% of routing protocols come in the opportunistic network. This article also comes with limitations, the description of included protocols (ex. DDFP, FCMA, D-SEMA) for the different networks was not included. The simulation environment for the protocols is also not used in this paper. In future work, a systematic literature review with the implementation of novel protocols will be considered.