diff --git a/build.gradle b/build.gradle
index 902461f..3c3e06e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -27,7 +27,6 @@ dependencies {
     implementation 'org.springframework.session:spring-session-core'
     compile group: 'org.apache.commons', name: 'commons-lang3', version: '3.7'
     compile group: 'commons-io', name: 'commons-io', version: '2.6'
-    compile group: 'com.google.guava', name: 'guava', version: '11.0.2'
     compile 'org.pcap4j:pcap4j-core:1.+'
     compile 'org.pcap4j:pcap4j-packetfactory-static:1.+'
     compileOnly 'org.projectlombok:lombok'
diff --git a/src/main/java/ru/serega6531/packmate/service/PatternService.java b/src/main/java/ru/serega6531/packmate/service/PatternService.java
index ba003c1..cf9da0d 100644
--- a/src/main/java/ru/serega6531/packmate/service/PatternService.java
+++ b/src/main/java/ru/serega6531/packmate/service/PatternService.java
@@ -4,16 +4,18 @@ import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Lazy;
+import org.springframework.security.crypto.codec.Hex;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 import ru.serega6531.packmate.model.FoundPattern;
 import ru.serega6531.packmate.model.Pattern;
-import ru.serega6531.packmate.model.enums.PatternDirectionType;
 import ru.serega6531.packmate.model.Stream;
+import ru.serega6531.packmate.model.enums.PatternDirectionType;
 import ru.serega6531.packmate.model.enums.PatternSearchType;
 import ru.serega6531.packmate.model.enums.SubscriptionMessageType;
 import ru.serega6531.packmate.model.pojo.SubscriptionMessage;
 import ru.serega6531.packmate.repository.PatternRepository;
+import ru.serega6531.packmate.utils.Bytes;
 
 import java.util.*;
 import java.util.regex.Matcher;
@@ -51,20 +53,19 @@ public class PatternService {
     }
 
     public Set<FoundPattern> findMatches(byte[] bytes, boolean incoming) {
-        String content = new String(bytes);
-
         return patterns.values().stream()
                 .filter(p -> p.getDirectionType() == (incoming ? PatternDirectionType.INPUT : PatternDirectionType.OUTPUT)
                         || p.getDirectionType() == PatternDirectionType.BOTH)
-                .map(pattern -> match(pattern, content))
+                .map(pattern -> match(pattern, bytes))
                 .flatMap(List::stream)
                 .collect(Collectors.toSet());
     }
 
-    private List<FoundPattern> match(Pattern pattern, String content) {
+    private List<FoundPattern> match(Pattern pattern, byte[] bytes) {
         List<FoundPattern> found = new ArrayList<>();
 
         if (pattern.getSearchType() == PatternSearchType.REGEX) {
+            String content = new String(bytes);
             final java.util.regex.Pattern regex = compilePattern(pattern);
             final Matcher matcher = regex.matcher(content);
 
@@ -78,9 +79,10 @@ public class PatternService {
 
             return found;
         } else if (pattern.getSearchType() == PatternSearchType.SUBSTRING) {
+            String content = new String(bytes);
             int startSearch = 0;
-
             final String value = pattern.getValue();
+
             while (true) {
                 int start = StringUtils.indexOfIgnoreCase(content, value, startSearch);
 
@@ -98,8 +100,25 @@ public class PatternService {
                 startSearch = end + 1;
             }
         } else {  // SUBBYTES
-            // TODO
-            return found;
+            int startSearch = 0;
+            final byte[] value = Hex.decode(pattern.getValue());
+
+            while (true) {
+                int start = Bytes.indexOf(bytes, value, startSearch, bytes.length);
+
+                if (start == -1) {
+                    return found;
+                }
+
+                int end = start + value.length - 1;
+                found.add(FoundPattern.builder()
+                        .patternId(pattern.getId())
+                        .startPosition(start)
+                        .endPosition(end)
+                        .build());
+
+                startSearch = end + 1;
+            }
         }
     }
 
diff --git a/src/main/java/ru/serega6531/packmate/service/StreamService.java b/src/main/java/ru/serega6531/packmate/service/StreamService.java
index ce4aed2..b336c96 100644
--- a/src/main/java/ru/serega6531/packmate/service/StreamService.java
+++ b/src/main/java/ru/serega6531/packmate/service/StreamService.java
@@ -1,6 +1,5 @@
 package ru.serega6531.packmate.service;
 
-import com.google.common.primitives.Bytes;
 import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.io.IOUtils;
@@ -17,6 +16,7 @@ import ru.serega6531.packmate.model.pojo.Pagination;
 import ru.serega6531.packmate.model.pojo.SubscriptionMessage;
 import ru.serega6531.packmate.model.pojo.UnfinishedStream;
 import ru.serega6531.packmate.repository.StreamRepository;
+import ru.serega6531.packmate.utils.Bytes;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
diff --git a/src/main/java/ru/serega6531/packmate/utils/Bytes.java b/src/main/java/ru/serega6531/packmate/utils/Bytes.java
new file mode 100644
index 0000000..1d8b647
--- /dev/null
+++ b/src/main/java/ru/serega6531/packmate/utils/Bytes.java
@@ -0,0 +1,26 @@
+package ru.serega6531.packmate.utils;
+
+public class Bytes {
+
+    public static int indexOf(byte[] array, byte[] target) {
+        return indexOf(array, target, 0, array.length);
+    }
+
+    public static int indexOf(byte[] array, byte[] target, int start, int end) {
+        if (target.length == 0) {
+            return 0;
+        }
+
+        outer:
+        for (int i = start; i < end - target.length + 1; i++) {
+            for (int j = 0; j < target.length; j++) {
+                if (array[i + j] != target[j]) {
+                    continue outer;
+                }
+            }
+            return i;
+        }
+        return -1;
+    }
+
+}