diff --git a/binding/c/main.c b/binding/c/main.c
index ad11cf7..a209da3 100644
--- a/binding/c/main.c
+++ b/binding/c/main.c
@@ -110,6 +110,11 @@ void test_search(int argc, char *argv[]) {
     long s_time, c_time;
     unsigned int ip;
     char line[512] = {'\0'}, region[512] = {'\0'};
+
+    // ip parse
+    xdb_ip_version_t *version;
+    bytes_ip_t ip_bytes[16] = {'\0'};
+
     searcher_test_t test;
 
     for (i = 2; i < argc; i++) {
@@ -173,13 +178,14 @@ void test_search(int argc, char *argv[]) {
             break;
         }
 
-        if (xdb_check_ip(line, &ip) != 0) {
+        version = xdb_parse_ip(line, ip_bytes, sizeof(ip_bytes));
+        if (version == NULL) {
             printf("invalid ip address `%s`\n", line);
             continue;
         }
 
         s_time = xdb_now();
-        err = xdb_search(&test.searcher, ip, region, sizeof(region));
+        err = xdb_search(&test.searcher, ip_bytes, version->bytes, region, sizeof(region));
         if (err != 0) {
             printf("{err: %d, io_count: %d}\n", err, xdb_get_io_count(&test.searcher));
         } else {
@@ -200,9 +206,15 @@ void test_bench(int argc, char *argv[]) {
     FILE *handle;
     char line[1024] = {'\0'}, sip_str[16] = {'\0'}, eip_str[16] = {'\0'};
     char src_region[512] = {'\0'}, region_buffer[512] = {'\0'};
-    unsigned int sip, eip, ip_list[2];
     int count = 0, took;
     long s_time, t_time, c_time = 0;
+
+    // ip parse
+    xdb_ip_version_t *s_version, *e_version;
+    bytes_ip_t sip_bytes[16] = {'\0'}, eip_bytes[16] = {'\0'};
+    string_ip_t ip_string[INET6_ADDRSTRLEN] = {'\0'};
+    bytes_ip_t *ip_list[2];
+
     searcher_test_t test;
 
     for (i = 2; i < argc; i++) {
@@ -269,38 +281,44 @@ void test_bench(int argc, char *argv[]) {
             return;
         }
 
-        if (xdb_check_ip(sip_str, &sip) != 0) {
+        s_version = xdb_parse_ip(sip_str, sip_bytes, sizeof(sip_bytes));
+        if (s_version == NULL) {
             printf("invalid start ip `%s`\n", sip_str);
             return;
         }
 
-        if (xdb_check_ip(eip_str, &eip) != 0) {
+        e_version = xdb_parse_ip(eip_str, eip_bytes, sizeof(eip_bytes));
+        if (e_version == NULL) {
             printf("invalid end ip `%s`\n", sip_str);
             return;
         }
 
-        if (sip > eip) {
+        if (s_version->id != e_version->id) {
+            printf("start ip and end ip version not match for line `%s`\n", line);
+            return;
+        }
+
+        if (xdb_ip_sub_compare(sip_bytes, s_version->bytes, eip_bytes, 0) > 0) {
             printf("start ip(%s) should not be greater than end ip(%s)\n", sip_str, eip_str);
             return;
         }
 
-        ip_list[0] = sip;
-        ip_list[1] = eip;
+        ip_list[0] = sip_bytes;
+        ip_list[1] = eip_bytes;
         for (i = 0; i < 2; i++) {
             t_time = xdb_now();
-            err = xdb_search(&test.searcher, ip_list[i], region_buffer, sizeof(region_buffer));
+            err = xdb_search(&test.searcher, ip_list[i], s_version->bytes, region_buffer, sizeof(region_buffer));
+            c_time += xdb_now() - t_time;
             if (err != 0) {
-                xdb_long2ip(ip_list[i], sip_str);
-                printf("failed to search ip `%s` with errno=%d\n", sip_str, err);
+                xdb_ip_to_string(ip_list[i], s_version->bytes, ip_string, sizeof(ip_string));
+                printf("failed to search ip `%s` with errno=%d\n", ip_string, err);
                 return;
             }
 
-            c_time += xdb_now() - t_time;
-
             // check the region info
             if (strcmp(region_buffer, src_region) != 0) {
-                xdb_long2ip(ip_list[i], sip_str);
-                printf("failed to search(%s) with (%s != %s)\n", sip_str, region_buffer, src_region);
+                xdb_ip_to_string(ip_list[i], s_version->bytes, ip_string, sizeof(ip_string));
+                printf("failed to search(%s) with (%s != %s)\n", ip_string, region_buffer, src_region);
                 return;
             }
 
diff --git a/binding/c/test_util b/binding/c/test_util
index 1b0c79f..8ae3a2e 100755
Binary files a/binding/c/test_util and b/binding/c/test_util differ
diff --git a/binding/c/test_util.c b/binding/c/test_util.c
index 0d56c7f..ea39248 100644
--- a/binding/c/test_util.c
+++ b/binding/c/test_util.c
@@ -68,6 +68,7 @@ void test_parse_ip() {
     };
 
     int errcode;
+    xdb_ip_version_t *version;
     bytes_ip_t ip_bytes[16] = {'\0'};
     string_ip_t ip_string[INET6_ADDRSTRLEN] = {'\0'};
 
@@ -82,14 +83,14 @@ void test_parse_ip() {
             break;
         }
 
-        errcode = xdb_parse_ip(ip_list[i], ip_bytes, sizeof(ip_bytes));
-        if (errcode == -1) {
+        version = xdb_parse_ip(ip_list[i], ip_bytes, sizeof(ip_bytes));
+        if (version == NULL) {
             printf("failed to parse ip `%s`\n", ip_list[i]);
             continue;
         }
 
-        xdb_ip_to_string(ip_bytes, errcode, ip_string, sizeof(ip_string));
-        printf("ip: %s (version=v%d), toString: %s\n", ip_list[i], errcode, ip_string);
+        xdb_ip_to_string(ip_bytes, version->bytes, ip_string, sizeof(ip_string));
+        printf("ip: %s (version=v%d), toString: %s\n", ip_list[i], version->id, ip_string);
     }
 
     // clean up the winsock
@@ -116,7 +117,8 @@ void test_ip_compare() {
     struct ip_pair *pair_ptr = NULL;
     bytes_ip_t sip_bytes[16] = {'\0'};
     bytes_ip_t eip_bytes[16] = {'\0'};
-    int sip_version, eip_version, bytes, errcode;
+    xdb_ip_version_t *s_version, *e_version;
+    int bytes, errcode;
 
     // init the sock env (for windows)
     if ((errcode = xdb_init_winsock()) != 0) {
@@ -130,23 +132,27 @@ void test_ip_compare() {
             break;
         }
 
-        sip_version = xdb_parse_ip(pair_ptr->sip, sip_bytes, sizeof(sip_bytes));
-        if (sip_version == -1) {
+        s_version = xdb_parse_ip(pair_ptr->sip, sip_bytes, sizeof(sip_bytes));
+        if (s_version == NULL) {
             printf("failed to parse sip `%s`", pair_ptr->sip);
             continue;
         }
 
-        eip_version = xdb_parse_ip(pair_ptr->eip, eip_bytes, sizeof(eip_bytes));
-        if (eip_version == -1) {
+        e_version = xdb_parse_ip(pair_ptr->eip, eip_bytes, sizeof(eip_bytes));
+        if (e_version == NULL) {
             printf("failed to parse eip `%s`", pair_ptr->eip);
             continue;
         }
 
-        bytes = sip_version == xdb_ipv4_version_no ? xdb_ipv4_bytes : xdb_ipv6_bytes;
+        if (s_version->id != e_version->id) {
+            printf("sip and eip version not match `%s` != `%s`\n", s_version->name, e_version->name);
+            continue;
+        }
+
         printf(
             "ip_sub_compare(%s, %s): %d\n", 
             pair_ptr->sip, pair_ptr->eip, 
-            xdb_ip_sub_compare(sip_bytes, bytes, eip_bytes, 0)
+            xdb_ip_sub_compare(sip_bytes, s_version->bytes, eip_bytes, 0)
         );
     }
 
diff --git a/binding/c/xdb_api.h b/binding/c/xdb_api.h
index 5763e2e..d0f7338 100644
--- a/binding/c/xdb_api.h
+++ b/binding/c/xdb_api.h
@@ -53,6 +53,29 @@
 typedef char string_ip_t;
 typedef unsigned char bytes_ip_t;
 
+// --- ip version
+#define XDB_IPv4 (xdb_version_ipv4())
+#define XDB_IPv6 (xdb_version_ipv6())
+typedef int (* ip_compare_fn_t) (const bytes_ip_t *, int, const char *, int);
+struct xdb_ip_version_entry {
+    int id;                 // version id
+    char *name;             // version name
+    int bytes;              // ip bytes number
+    int segment_index_size; // segment index size in bytes
+
+    // function to compare two ips
+    ip_compare_fn_t ip_compare;
+};
+typedef struct xdb_ip_version_entry xdb_ip_version_t;
+
+XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv4();
+XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv6();
+
+XDB_PUBLIC(int) xdb_ip_version_is_v4(const xdb_ip_version_t *);
+XDB_PUBLIC(int) xdb_ip_version_is_v6(const xdb_ip_version_t *);
+
+// --- END ip version
+
 // --- xdb util functions
 
 // to compatiable with the windows
@@ -77,16 +100,16 @@ XDB_PUBLIC(void) xdb_long2ip(unsigned int, char *);
 
 
 // parse the specified IP address to byte array.
-// returns: 4 for valid ipv4, 16 for valid ipv6, or -1 for failed
-XDB_PUBLIC(int) xdb_parse_ip(const string_ip_t *, bytes_ip_t *, size_t);
+// returns: xdb_ip_version_t for valid ipv4 / ipv6, or NULL for failed
+XDB_PUBLIC(xdb_ip_version_t *) xdb_parse_ip(const string_ip_t *, bytes_ip_t *, size_t);
 
 // parse the specified IPv4 address to byte array
-// returns: 4 for valid ipv4, or -1 for failed
-XDB_PUBLIC(int) xdb_parse_v4_ip(const string_ip_t *, bytes_ip_t *, size_t);
+// returns: xdb_ip_version_t for valid ipv4, or NULL for failed
+XDB_PUBLIC(xdb_ip_version_t *) xdb_parse_v4_ip(const string_ip_t *, bytes_ip_t *, size_t);
 
 // parse the specified IPv6 address to byte array
-// returns: 16 for valid ipv6, or -1 for failed
-XDB_PUBLIC(int) xdb_parse_v6_ip(const string_ip_t *, bytes_ip_t *, size_t);
+// returns: xdb_ip_version_t for valid ipv6, or NULL for failed
+XDB_PUBLIC(xdb_ip_version_t *) xdb_parse_v6_ip(const string_ip_t *, bytes_ip_t *, size_t);
 
 // convert a specified ip bytes to humen-readable string.
 // returns: 0 for success or -1 for failed.
@@ -101,30 +124,10 @@ XDB_PUBLIC(int) xdb_v6_ip_to_string(const bytes_ip_t *, char *, size_t);
 // compare the specified ip bytes with another ip bytes in the specified buff from offset.
 // ip args must be the return value from #xdb_parse_ip.
 // returns: -1 if ip1 < ip2, 1 if ip1 > ip2 or 0
-XDB_PUBLIC(int) xdb_ip_sub_compare(const bytes_ip_t *, size_t, const char *, int);
+XDB_PUBLIC(int) xdb_ip_sub_compare(const bytes_ip_t *, int, const char *, int);
 
 // --- END xdb utils
 
-// --- ip version
-#define XDB_IPv4 (xdb_version_ipv4())
-#define XDB_IPv6 (xdb_version_ipv6())
-typedef int (* ip_compare_fn_t) (const bytes_ip_t *, size_t, const char *, int);
-struct xdb_ip_version_entry {
-    int id;                 // version id
-    char *name;             // version name
-    int bytes;              // ip bytes number
-    int segment_index_size; // segment index size in bytes
-
-    // function to compare two ips
-    ip_compare_fn_t ip_compare;
-};
-typedef struct xdb_ip_version_entry xdb_ip_version_t;
-
-XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv4();
-XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv6();
-
-// --- END ip version
-
 
 // --- xdb buffer functions
 
@@ -218,7 +221,7 @@ XDB_PUBLIC(int) xdb_new_with_buffer(xdb_ip_version_t *, xdb_searcher_t *, const
 XDB_PUBLIC(void) xdb_close(void *);
 
 // xdb searcher search api define
-XDB_PUBLIC(int) xdb_search_by_string(xdb_searcher_t *, const char *, char *, size_t);
+XDB_PUBLIC(int) xdb_search_by_string(xdb_searcher_t *, const string_ip_t *, char *, size_t);
 
 XDB_PUBLIC(int) xdb_search(xdb_searcher_t *, const bytes_ip_t *, int, char *, size_t);
 
diff --git a/binding/c/xdb_searcher.c b/binding/c/xdb_searcher.c
index d49efef..275c30a 100644
--- a/binding/c/xdb_searcher.c
+++ b/binding/c/xdb_searcher.c
@@ -59,33 +59,34 @@ XDB_PUBLIC(void) xdb_close(void *ptr) {
 
 // --- xdb searcher search api define
 
-XDB_PUBLIC(int) xdb_search_by_string(xdb_searcher_t *xdb, const char *ip_string, char *region_buffer, size_t length) {
+XDB_PUBLIC(int) xdb_search_by_string(xdb_searcher_t *xdb, const string_ip_t *ip_string, char *region_buffer, size_t length) {
     bytes_ip_t ip_bytes[16] = {'\0'};
-    int versionNo = xdb_parse_ip(ip_string, ip_bytes, sizeof(ip_bytes));
-    if (versionNo == -1) {
+    xdb_ip_version_t *version = xdb_parse_ip(ip_string, ip_bytes, sizeof(ip_bytes));
+    if (version == NULL) {
         return 10;
     } else {
-        return xdb_search(xdb, ip_bytes, versionNo, region_buffer, length);
+        return xdb_search(xdb, ip_bytes, version->bytes, region_buffer, length);
     }
 }
 
-XDB_PUBLIC(int) xdb_search(xdb_searcher_t *xdb, const bytes_ip_t *ip_bytes, int byte_count, char *region_buffer, size_t length) {
+XDB_PUBLIC(int) xdb_search(xdb_searcher_t *xdb, const bytes_ip_t *ip_bytes, int ip_len, char *region_buffer, size_t length) {
     int il0, il1, idx, err, bytes, d_bytes;
     register int seg_index_size, l, h, m, p;
     unsigned int s_ptr, e_ptr, data_ptr, data_len;
     char vector_buffer[xdb_vector_index_size];
     char *segment_buffer = NULL;
+    string_ip_t sip_string[INET6_ADDRSTRLEN] = {'\0'}, eip_string[INET6_ADDRSTRLEN] = {'\0'};
 
     // ip version check
-    if (byte_count != xdb->version->bytes) {
+    if (ip_len != xdb->version->bytes) {
         return -1;
     }
 
     // some resets
     err = 0;
     data_len = 0;
-    bytes = byte_count;
-    d_bytes = byte_count << 1;
+    bytes   = xdb->version->bytes;
+    d_bytes = xdb->version->bytes << 1;
     xdb->io_count = 0;
 
     // locate the segment index block based on the vector index
@@ -108,7 +109,7 @@ XDB_PUBLIC(int) xdb_search(xdb_searcher_t *xdb, const bytes_ip_t *ip_bytes, int
         e_ptr = xdb_le_get_uint32(vector_buffer, 4);
     }
 
-    // printf("s_ptr=%u, e_ptr=%u\n", s_ptr, e_ptr);
+    printf("s_ptr=%u, e_ptr=%u\n", s_ptr, e_ptr);
     // binary search to get the final region info
     seg_index_size = xdb->version->segment_index_size;
     segment_buffer = xdb_malloc(seg_index_size);
@@ -129,10 +130,14 @@ XDB_PUBLIC(int) xdb_search(xdb_searcher_t *xdb, const bytes_ip_t *ip_bytes, int
             goto done;
         }
 
+        xdb_ip_to_string(segment_buffer, bytes, sip_string, sizeof(sip_string));
+        xdb_ip_to_string(segment_buffer + bytes, bytes, eip_string, sizeof(eip_string));
+        printf("l=%d, h=%d, p=%d, sip: %s, eip: %s\n", l, h, p, sip_string, eip_string);
+
         // decode the data fields as needed
-        if (xdb_ip_sub_compare(ip_bytes, byte_count, segment_buffer, 0) < 0) {
+        if (xdb->version->ip_compare(ip_bytes, bytes, segment_buffer, 0) < 0) {
             h = m - 1;
-        } else if (xdb_ip_sub_compare(ip_bytes, byte_count, segment_buffer, bytes) > 0) {
+        } else if (xdb->version->ip_compare(ip_bytes, bytes, segment_buffer, bytes) > 0) {
             l = m + 1;
         } else {
             data_len = xdb_le_get_uint16(segment_buffer, d_bytes);
@@ -141,7 +146,7 @@ XDB_PUBLIC(int) xdb_search(xdb_searcher_t *xdb, const bytes_ip_t *ip_bytes, int
         }
     }
 
-    // printf("data_len=%u, data_ptr=%u\n", data_len, data_ptr);
+    printf("data_len=%u, data_ptr=%u\n", data_len, data_ptr);
     if (data_len == 0) {
         goto done;
     }
diff --git a/binding/c/xdb_util.c b/binding/c/xdb_util.c
index 343f25e..6699bc0 100644
--- a/binding/c/xdb_util.c
+++ b/binding/c/xdb_util.c
@@ -58,6 +58,55 @@ XDB_PUBLIC(int) xdb_init_winsock() {return 0;}
 XDB_PUBLIC(void) xdb_clean_winsock() {}
 #endif
 
+// --- ip version
+
+// ip compare for IPv4
+// ip1 - with Big endian byte order parsed from an input
+// ip2 - with Little endian byte order read from the xdb index.
+// to compatiable with the Little Endian encoded IPv4 on xdb 2.0.
+XDB_PRIVATE(int) _ipv4_sub_compare(const bytes_ip_t *ip_bytes, int bytes, const char *buffer, int offset) {
+    register int i0, i1;
+    for (int i = 0, j = offset + bytes - 1; i < bytes; i++, j--) {
+        i0 = ip_bytes[i];
+        i1 = buffer[j] & 0xFF;
+        if (i0 > i1) {
+            return 1;
+        } else if (i0 < i1) {
+            return -1;
+        }
+    }
+    return 0;
+}
+
+static xdb_ip_version_t _ip_version_list[] = {
+    // 14 = 4 + 4 + 2 + 4
+    {xdb_ipv4_version_no, "IPv4", xdb_ipv4_bytes, 14, _ipv4_sub_compare},
+
+    // 38 = 16 + 16 + 2 + 4
+    {xdb_ipv6_version_no, "IPv6", xdb_ipv6_bytes, 38, xdb_ip_sub_compare},
+
+    // END
+    {0, NULL, 0, 0, NULL}
+};
+
+XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv4() {
+    return &_ip_version_list[0];
+}
+
+XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv6() {
+    return &_ip_version_list[1];
+}
+
+XDB_PUBLIC(int) xdb_ip_version_is_v4(const xdb_ip_version_t *version) {
+    return version->id == xdb_ipv4_version_no;
+}
+
+XDB_PUBLIC(int) xdb_ip_version_is_v6(const xdb_ip_version_t *version) {
+    return version->id == xdb_ipv6_version_no;
+}
+
+// --- END ip version
+
 XDB_PUBLIC(long) xdb_now() {
     struct timeval c_time;
     gettimeofday(&c_time, NULL);
@@ -80,46 +129,7 @@ XDB_PUBLIC(int) xdb_le_get_uint16(const char *buffer, int offset) {
     );
 }
 
-// string ip to unsigned int
-static int shiftIndex[4] = {24, 16, 8, 0};
-XDB_PUBLIC(int) xdb_check_ip(const char *src_ip, unsigned int *dst_ip) {
-    char c;
-    int i, n, ip = 0;
-    const char *ptr = src_ip;
-    for (i = 0; i < 4; i++) {
-        n = 0;
-        while (1) {
-            c = *ptr;
-            ptr++;
-            if (c >= '0' && c <= '9') {
-                n *= 10;
-                n += c - '0';
-            } else if ((i < 3 && c == '.') || i == 3) {
-                // stopping at the '.' but ignore the tailing chars
-                // after the 3rd one (auto clean the tailing none-integer ?).
-                break;
-            } else {
-                return 1;
-            }
-        }
-
-        if (n > 0xFF) {
-            return 2;
-        }
-
-        ip |= (n << shiftIndex[i]);
-    }
-
-    *dst_ip = ip;
-    return 0;
-}
-
-// unsigned int ip to string ip
-XDB_PUBLIC(void) xdb_long2ip(unsigned int ip, char *buffer) {
-    sprintf(buffer, "%d.%d.%d.%d", (ip >> 24) & 0xFF, (ip >> 16) & 0xFF, (ip >> 8) & 0xFF, ip & 0xFF);
-}
-
-XDB_PUBLIC(int) xdb_parse_ip(const string_ip_t *ip_string, bytes_ip_t *buffer, size_t length) {
+XDB_PUBLIC(xdb_ip_version_t *) xdb_parse_ip(const string_ip_t *ip_string, bytes_ip_t *buffer, size_t length) {
     // version check
     if (strchr(ip_string, '.') != NULL && strchr(ip_string, ':') == NULL) {
         return xdb_parse_v4_ip(ip_string, buffer, length);
@@ -127,19 +137,19 @@ XDB_PUBLIC(int) xdb_parse_ip(const string_ip_t *ip_string, bytes_ip_t *buffer, s
         return xdb_parse_v6_ip(ip_string, buffer, length);
     }
 
-    return -1;
+    return NULL;
 }
 
-XDB_PUBLIC(int) xdb_parse_v4_ip(const string_ip_t *ip_string, bytes_ip_t *buffer, size_t length) {
+XDB_PUBLIC(xdb_ip_version_t *) xdb_parse_v4_ip(const string_ip_t *ip_string, bytes_ip_t *buffer, size_t length) {
     struct in_addr addr;
 
     // buffer length checking
     if (length < xdb_ipv4_bytes) {
-        return -1;
+        return NULL;
     }
 
     if (inet_pton(AF_INET, ip_string, &addr) != 1) {
-        return -1;
+        return NULL;
     }
 
     // encode the address to buffer with big endian byte bufffer.
@@ -147,29 +157,29 @@ XDB_PUBLIC(int) xdb_parse_v4_ip(const string_ip_t *ip_string, bytes_ip_t *buffer
     buffer[1] = (addr.s_addr >> 8) & 0xFF;
     buffer[2] = (addr.s_addr >> 16) & 0xFF;
     buffer[3] = (addr.s_addr >> 24) & 0xFF;
-    return xdb_ipv4_version_no;
+    return XDB_IPv4;
 }
 
-XDB_PUBLIC(int) xdb_parse_v6_ip(const string_ip_t *ip_string, bytes_ip_t *buffer, size_t length) {
+XDB_PUBLIC(xdb_ip_version_t *) xdb_parse_v6_ip(const string_ip_t *ip_string, bytes_ip_t *buffer, size_t length) {
     struct  in6_addr addr;
 
     // buffer length checking
     if (length < xdb_ipv6_bytes) {
-        return -1;
+        return NULL;
     }
 
     if (inet_pton(AF_INET6, ip_string, &addr) != 1) {
-        return -1;
+        return NULL;
     }
 
     memcpy(buffer, addr.s6_addr, xdb_ipv6_bytes);
-    return xdb_ipv6_version_no;
+    return XDB_IPv6;
 }
 
-XDB_PUBLIC(int) xdb_ip_to_string(const bytes_ip_t *ip_bytes, int version, char *ip_string, size_t length) {
-    if (version == xdb_ipv4_version_no) {
+XDB_PUBLIC(int) xdb_ip_to_string(const bytes_ip_t *ip_bytes, int bytes, char *ip_string, size_t length) {
+    if (bytes == xdb_ipv4_bytes) {
         return xdb_v4_ip_to_string(ip_bytes, ip_string, length);
-    } else if (version == xdb_ipv6_version_no) {
+    } else if (bytes == xdb_ipv6_bytes) {
         return xdb_v6_ip_to_string(ip_bytes, ip_string, length);
     }
 
@@ -209,9 +219,9 @@ XDB_PUBLIC(int) xdb_v6_ip_to_string(const bytes_ip_t *ip_bytes, char *ip_string,
     return 0;
 }
 
-XDB_PUBLIC(int) xdb_ip_sub_compare(const bytes_ip_t *ip1, size_t length, const char *buffer, int offset) {
+XDB_PUBLIC(int) xdb_ip_sub_compare(const bytes_ip_t *ip1, int bytes, const char *buffer, int offset) {
     register int i, i1, i2;
-    for (i = 0; i < length; i++) {
+    for (i = 0; i < bytes; i++) {
         i1 = ip1[i];
         i2 = buffer[offset + i] & 0xFF;
         if (i1 > i2) {
@@ -389,23 +399,3 @@ XDB_PUBLIC(void) xdb_free_content(void *ptr) {
 }
 
 // --- End
-
-// --- ip version
-static xdb_ip_version_t _ip_version_list[] = {
-    // 14 = 4 + 4 + 2 + 4
-    {xdb_ipv4_version_no, "IPv4", xdb_ipv4_bytes, 14, NULL},
-
-    // 38 = 16 + 16 + 2 + 4
-    {xdb_ipv6_version_no, "IPv6", xdb_ipv6_bytes, 38, NULL},
-
-    // END
-    {0, NULL, 0, 0, NULL}
-};
-
-XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv4() {
-    return &_ip_version_list[0];
-}
-
-XDB_PUBLIC(xdb_ip_version_t *) xdb_version_ipv6() {
-    return &_ip_version_list[1];
-}
\ No newline at end of file